Application 2: Why preventing your opponent's good move is slightly lower priority than them doing it, a case for kiai
This is an example where kiai or a rush of blood to the head/balls does lead to good play. The addition of the 3.5) answer approach to 3-4 (prevent press) and 5.5) answer approach to 4-4 (prevent double approach) were
in response to someone on reddit asking where they would fit in. I put them just below the class of the good thing they prevent your opponent doing, rather than at the same level. That's because if you treat them as the same, your opponent is making small gains in sente, in that they lessen how good your next move in that area is, whilst retaining sente. An example:
$$Bc
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$$ | . . . 2 . . . . . . . . . 9 . . . . . |
$$ | . . . , 8 . . . . , . . . . . , 1 . . |
$$ | . . 7 . . . . . . . . . . . . . . . . |
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$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . , . 6 . . . , . . . . . , . . . |
$$ | . . . 4 . . . . . . . . . . . 3 . . . |
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- Click Here To Show Diagram Code
[go]$$Bc
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$$ | . . . 2 . . . . . . . . . 9 . . . . . |
$$ | . . . , 8 . . . . , . . . . . , 1 . . |
$$ | . . 7 . . . . . . . . . . . . . . . . |
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$$ | . . 0 . . . . . . . . . . . . . . . . |
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$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . , . 6 . . . , . . . . . , . . . |
$$ | . . . 4 . . . . . . . . . . . 3 . . . |
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$$ +---------------------------------------+[/go]
Moves 1 to 4 take the empty corners at 3-4, all following the gospel at class 1. The reason I picked 3-4s for this example is, as old opening theory also taught us, they are 'unfinished corners' so the next play there of an approach/enclosure is class 2, above a class 4 approach/invade of a 4-4, the board has 4 hot areas. Black 5 follows the gospel with one of several class 2 choices available. If white answers with the patient 6 (class 3.5) then black can grab another class 2 approach at 7, white answers patiently again, and then black 9 grabs another class 2, a shimari this time (top right is slightly better than lower right, due to preventing white's class 2 approach there which works well with 8 to develop top side, this direction of play decision the gospel can't help you with, but if you pick lower right shimari it's not much worse). White 10 didn't follow the gospel by approaching at r5, but is also a good move and illustrates the point this move results in a position, with tally 3-1 to white, that is not quite as good as the same net surplus of 2 white moves of 2-0 for a shimari if black didn't approach there but directly played 7:
$$Bc
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$$ | . . . 2 . . . . . . . . . 7 . . . . . |
$$ | . . . , . . . . . , . . . . . , 1 . . |
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$$ | . . 8 . . . . . . . . . . . . . . . . |
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$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . , . 6 . . . , . . . . . , . . . |
$$ | . . . 4 . . . . . . . . . . . 3 . . . |
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$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$Bc
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$$ | . . . 2 . . . . . . . . . 7 . . . . . |
$$ | . . . , . . . . . , . . . . . , 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 8 . . . . . . . . . . . . . . . . |
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$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . , . 6 . . . , . . . . . , . . . |
$$ | . . . 4 . . . . . . . . . . . 3 . . . |
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$$ +---------------------------------------+[/go]
So if white followed the gospel for 6 there are a few class 2 choices, such as taking the one shimari he can, as go Seigen liked to do on this left side facing 3-4s position, or approaches at
a or
b. To avoid letting black making small gains in sente, white takes an equally valuable class 2 move and we can end up with the kiai-fest of lots or approaches all around the board.
$$Bc
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$$ | . . . O . . . . . . . . . . a . . . . |
$$ | . . . , . . . . . , . . . . . , X . . |
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$$ | . . 6 . . . . . . . . . . . . . . . . |
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$$ | . . 5 . . . . . . . . . . . . . b . . |
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$$ | . . . O . . . . . . . . . . . X . . . |
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$$ +---------------------------------------+
- Click Here To Show Diagram Code
[go]$$Bc
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . a . . . . |
$$ | . . . , . . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 . . . . . . . . . . . . . . . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 5 . . . . . . . . . . . . . b . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . O . . . . . . . . . . . X . . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
One caveat to the above argument is the gospel is colour-agnostic, but in reality white has komi so a more patient style of some class 3.5s before class 2s is not so bad if it gives you the kind of game you can control better.