In my previous post, I explained why I didn't choose a particular losing move. In this post, I endeavor to explain how that realization led me to the best move - and probably the only move that does not lose.
I that previous post, we were looking at this position:
Move 7 is heavy. It does not increase the liberties of anything, and it attempts to save a stone that does not have to be saved - D7 either has to be saved OR rendered useless as an eye.
I was looking at this position, dismayed that such a vulgar move was necessary. I started doing sort of tewari analysis, asking myself where other stones should be to make 7 less ugly.
Making D7 a false eye without having to save it would be far more elegant. That, of course, means getting two of the four diagonal neighboring points.
In other words, once he plays 4, I don't want a stone at 'a'; I want it at 'b'. If I can hold both 5 and 'b', then D7 becomes a false eye if he captures it.
So I concluded that a stone at 5 would work. It attempts to extricate D7 by connecting outward via either 'c' or 'd'. And it does not link it's fate to D7 by connecting solidly.
If white is really determined to not let D7 escape, then 3 as shown above is in one of the four crucial points to make D7 a false eye. If I haven't wasted a move in the wrong place, I can get a second one of the four.
It looks like this:
Black either saves D7 by killing 4, or makes it a false eye by connecting 7 eastward.
It was this line of thought - with a lot of useless side branches - that led me to choose E6.
I that previous post, we were looking at this position:
$$Bcm101 Prisoners: 
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . 6 . X X . . . . . . . . X . . |
$$ | O O O X 4 3 . . . . . . . . . . . . . |
$$ | X X O 7 5 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . 6 . X X . . . . . . . . X . . |
$$ | O O O X 4 3 . . . . . . . . . . . . . |
$$ | X X O 7 5 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Bcm101 Prisoners:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . 6 . X X . . . . . . . . X . . |
$$ | O O O X 4 3 . . . . . . . . . . . . . |
$$ | X X O 7 5 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Move 7 is heavy. It does not increase the liberties of anything, and it attempts to save a stone that does not have to be saved - D7 either has to be saved OR rendered useless as an eye.
I was looking at this position, dismayed that such a vulgar move was necessary. I started doing sort of tewari analysis, asking myself where other stones should be to make 7 less ugly.
Making D7 a false eye without having to save it would be far more elegant. That, of course, means getting two of the four diagonal neighboring points.
$$Bm1 I need two of the circled points
$$ . . . . . . .
$$ . . C O C . .
$$ . . O . O . .
$$ . . C O C . .
$$ . . . . . . .
$$ . . . . . . .
$$ . . C O C . .
$$ . . O . O . .
$$ . . C O C . .
$$ . . . . . . .
- Click Here To Show Diagram Code
[go]$$Bm1 I need two of the circled points
$$ . . . . . . .
$$ . . C O C . .
$$ . . O . O . .
$$ . . C O C . .
$$ . . . . . . .[/go]
In other words, once he plays 4, I don't want a stone at 'a'; I want it at 'b'. If I can hold both 5 and 'b', then D7 becomes a false eye if he captures it.
$$Bcm101 Prisoners: 
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . b . X X . . . . . . . . X . . |
$$ | O O O X 4 a . . . . . . . . . . . . . |
$$ | X X O . 5 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . b . X X . . . . . . . . X . . |
$$ | O O O X 4 a . . . . . . . . . . . . . |
$$ | X X O . 5 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Bcm101 Prisoners:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . b . X X . . . . . . . . X . . |
$$ | O O O X 4 a . . . . . . . . . . . . . |
$$ | X X O . 5 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
So I concluded that a stone at 5 would work. It attempts to extricate D7 by connecting outward via either 'c' or 'd'. And it does not link it's fate to D7 by connecting solidly.
$$Bcm101 Prisoners: 
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . . . X X . . . . . . . . X . . |
$$ | O O O X . c . . . . . . . . . . . . . |
$$ | X X O . 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . d . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . . . X X . . . . . . . . X . . |
$$ | O O O X . c . . . . . . . . . . . . . |
$$ | X X O . 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . d . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Bcm101 Prisoners:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . . . X X . . . . . . . . X . . |
$$ | O O O X . c . . . . . . . . . . . . . |
$$ | X X O . 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . d . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
If white is really determined to not let D7 escape, then 3 as shown above is in one of the four crucial points to make D7 a false eye. If I haven't wasted a move in the wrong place, I can get a second one of the four.
It looks like this:
$$Bcm101 Prisoners: 
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . 7 . X X . . . . . . . . X . . |
$$ | O O O X 4 . . . . . . . . . . . . . . |
$$ | X X O 6 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . 5 . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . 7 . X X . . . . . . . . X . . |
$$ | O O O X 4 . . . . . . . . . . . . . . |
$$ | X X O 6 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . 5 . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Bcm101 Prisoners:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . 7 . X X . . . . . . . . X . . |
$$ | O O O X 4 . . . . . . . . . . . . . . |
$$ | X X O 6 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . 5 . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Black either saves D7 by killing 4, or makes it a false eye by connecting 7 eastward.
It was this line of thought - with a lot of useless side branches - that led me to choose E6.
$$Bcm101 Prisoners: 
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . . . X X . . . . . . . . X . . |
$$ | O O O X . . . . . . . . . . . . . . . |
$$ | X X O . 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . . . X X . . . . . . . . X . . |
$$ | O O O X . . . . . . . . . . . . . . . |
$$ | X X O . 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------
- Click Here To Show Diagram Code
[go]$$Bcm101 Prisoners:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . O . X . . O . . . . X . O . . |
$$ | . O . O . . . . X O . X . . . , X O . |
$$ | . . O O X X . . X O . . . . X . X . . |
$$ | . O . . O X . . . . O . O . . . . . . |
$$ | . X O O O X . O O . . . . . . . . . . |
$$ | . . X X X X X . . . . . . X . . X . . |
$$ | . . . . . O . . O . . . O X . O X . . |
$$ | . X . X X . X X O , . O . O O , . . . |
$$ | . O O O O O . . O . . . O . . X . . . |
$$ | . . . . . . X X . . . . . . . . X . . |
$$ | O O O X . . . . . . . . . . . . . . . |
$$ | X X O . 3 2 . . . X . . . O . . O . . |
$$ | 1 X O . . . . . . . . O . . . . . . . |
$$ | X O O X . X . . . , . . . . . O . . . |
$$ | X X X . . . . . X X . O . X . . . . . |
$$ | . . . . . . . . X O O . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Black don't have time to make two eyes with B1.
needed? Can't black play this: