Emeraldemon is correct about move 10. Here is a little more about why he is correct.
Suppose you asked two pros to play, and sat them down in front of this board:
- Click Here To Show Diagram Code
[go]$$c
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | O O O O O O O O O O O O O O O O O O O |
$$ | X X X X X X X X X X X X X X X X X X X |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | X X X X X X X X X X X X X X X X X X X |
$$ | O O O O O O O O O O O O O O O O O O O |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
White would take one look at the board and resign immediately. Although he has 76 guaranteed points, the influence of the black stones is worth so much more that white has no chance.
As a general rule of thumb, pros say that a stone in a wall is worth about 2.5 to 3 points. It varies greatly depending upon the circumstances.
If you apply that rule of thumb to a board like this:
- Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 1 2 . . . . . . . . . . . . . . . |
$$ | . . 3 X . . . . . , . . . . . X . . . |
$$ | . . 5 4 . . . . . . . . . . . . . . . |
$$ | . . 7 6 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
...you can see that white is making exactly two points of teritory per move. Black is making more than two points per move. So you would be happy to continue marching across the board side by side with him until the board starts to resemble the one above.
You can, as you know, hane and push him down like this:
- Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 1 2 . . . . . . . . . . . . . . . |
$$ | . . 3 X . . . . . , . . . . . X . . . |
$$ | . 5 4 . . . . . . . . . . . . . . . . |
$$ | . 7 6 . . . . . . . . . . . . . . . . |
$$ | a 9 8 . . . . . . . . . . . . . . . . |
$$ | . . 0 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
This looks even better for you. You are getting something around 3 points worth of influence every move, while he is getting a meager 1 point per move.
BUT, there is one little problem. You have a potential cutting point at D15. As long as he cannot exploit it, your wall is worth a lot. But if he can cut there, your wall converts from an asset into two juicy targets for him to kill.
So don't get greedy. You don't have to extract every possible advantage from this corner. Let him have one measly little point at 'a'. Keep your wall strong, and it is worth something like 15 points, give or take a little. His corner, under the best of circumstances, is worth maybe 10. You are ahead in this corner.