I was looking at 501 opening problems for the first time in awhile, and I was surprised by the answer. I would have invaded low, having banished the high invasion from my mind after reading Attack and Defense. However, the invasion does seem to work well on this board.

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[go]$$c The solution from the book.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . O . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . O 5 . . |
$$ | . . . . . . . . . . . . . . . 4 3 . . |
$$ | . . . . . . . . . . . . . . . 1 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . , X . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

What I'm wondering is the circumstances under which this invasion works, or anything else y'all know about it. I realize the two positions that follow are not very realistic games.

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[go]$$c
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . O . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . O 5 . . |
$$ | . . . . . . . . . . . . . . . 4 3 . . |
$$ | . . . . . . . . . . . . . . . 1 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . , X . . |
$$ | . . . . . . . . . X . . . . X . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Still feels ok with the shimari.

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[go]$$c
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . O . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . O 5 . . |
$$ | . . . . . . . . . . . . . . . 4 3 . . |
$$ | . . . . . . . . . . . . . . . 1 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , . X . . . , . . . . . X . . . |
$$ | . . . . . . . . . X . . . X . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I have a gut feeling that the open corner makes this bad, but I feel like I might as well throw darts at the board as choose moves for either player.

_________________
Occupy Babel!

The first and final games you posted look realistic. The game with the corner shimari does make white's play a little odd though.

Anyway, I wish I could help, but I don't know much about this invasion. All I know is that this invasion occurred in the 66th Honinbo game 3 - I can't find this game right now, but perhaps with more digging you can find it.

Edit: Found it here:

_________________
We don't know who we are; we don't know where we are.
Each of us woke up one moment and here we were in the darkness.
We're nameless things with no memory; no knowledge of what went before,
No understanding of what is now, no knowledge of what will be.

Funny, I watched that Honinbo game. I guess the invasion didn't register then.

The first game should look realistic. The authors took positions from actual games and from newspaper columns.

_________________
Occupy Babel!

You may be thinking about this position:

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[go]$$
$$ . . . . . . . .
$$ . . x B x O . .
$$ . O . x . . . .
$$ . . . . . . . .
$$ . . . . . . . .
$$ -------------[/go]

This is typically bad, you want to play at one of the 'x' points instead. That's because of the following variation:

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[go]$$W
$$ . . . . . . . .
$$ . . 6 B 3 O . .
$$ . O 4 1 2 . . a
$$ . . 7 5 . . . .
$$ . . . . . . . .
$$ -------------[/go]

This result is considered good for white, because white gained a lot of territory for not much influence in return. Note the absence of a black stone at 'a'

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[go]$$
$$ . . . . . . . . .
$$ . . . B . O . . .
$$ . O . . . . . X .
$$ . . . . . . . . .
$$ . . . . . . . . .
$$ -------------[/go]

But this situation is completely different, the additional black stone provides an easy escape route for .
Also note that black is not the only one having a stone at the "bad shape" spot .