Here is another game where we can regard the small avalanche as joseki.

GoGoD 1930-03-26j, Takahashi Shigeyuki, 3 dan (W) vs. Inoue Ichiro, 3 dan
- Click Here To Show Diagram Code
[go]$$Wcm8 Small avalanche blunder
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$$ | . . . . . . . . . . . . . . . . 7 . . |
$$ | . . . O . . . . . . . . . a X 2 5 . . |
$$ | . . . , . . . . . , . . . 4 O 1 X 6 . |
$$ | . . . . . . . . . . . . . . . . 3 8 . |
$$ | . . . . . . . . . . . . . . b 9 0 . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . c . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , X . . . . , . . . . . O . . . |
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$$ ---------------------------------------[/go]
OC, Elf prefers the outside hane at
a for

, but Takahashi's play was within the margin of error, IMHO — just barely, losing 4% to par. Somewhat surprisingly,

, the small avalanche hane, is Elf's top choice instead of the descent to
13. The rest of the plays are Elf's top choices until

, a traditional joseki play. Elf prefers the attachment at
b. When I was learning go the joseki with

was considered slightly inferior, but the approach to the bottom corner at
c would make up for that. Elf, however, thinks that

loses a whopping 19½% to par, which IMHO makes it a blunder.
- Click Here To Show Diagram Code
[go]$$Wcm18 Minor error
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . O . . . . . . . . . 1 X X O . . |
$$ | . . . , . . . . . , . . . X O O X X . |
$$ | . . . . . . . . . . . . . . . 2 O X . |
$$ | . . . . . . . . . . . . . . . O X . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , X . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Elf also regards

as a minor error, losing 5½% to par. You might find its recommendation interesting.
- Click Here To Show Diagram Code
[go]$$Bcm19 Elf's mainline variation for 
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . 4 6 O . . |
$$ | . . . O . . . . . . . . . O B B O . . |
$$ | . . . , . . . . . , . . 2 X O O X X . |
$$ | . . . . . . . . . . . . . 3 . 5 O X . |
$$ | . . . . . . . . . . . . . . 1 W X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , X . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Elf still likes the attachment. The result is that, while Black does not capture the

stone, White is forced to capture the

stones, and Black ends up with sente. Why didn't the humans come up with this?