Hi everyone!
I have some trouble with the evaluation of a corner sequence I never encountered before from a recent kgs game. It would be nice if some stronger players could comment on this. Although the result was not bad for me, it still somehow feels as if my opponent got away easy.

It started from here (I'm white):

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[go]$$W Starting position.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , . . . . . , . . . . . , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . . O . O . . . . . . . X . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

My idea was this (5 could also be at a):

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[go]$$W The plan.
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . 2 . . 4 . . |
$$ . . . X . 3 . |
$$ . . . . . . . |
$$ . . 5 . 1 . . |
$$ . . . . . . . |
$$ . . . a . . . |
$$ . . . . . . . |
$$ . . . , O . . |
$$ . . . . . . . |[/go]

Instead it went like this, which felt good for w:

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[go]$$W Black overplay?
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . 2 . . 7 . . |
$$ . . . X . 3 . |
$$ . . . . . . . |
$$ . . 5 . 1 . . |
$$ . . . . . . . |
$$ . . 6 . 4 . . |
$$ . . . . . . . |
$$ . . . , O . . |
$$ . . . . . . . |[/go]

Now black surprised me with 1. In retrospect, I think I should have resisted strongly with a. In the game I wanted to keep things simple but it seems white can handle the fight.

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[go]$$B unusual...
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . X . . O . . |
$$ . . . X . O . |
$$ . . . . 1 . . |
$$ . . O . O a . |
$$ . . . . . . . |
$$ . . X . X . . |
$$ . . . . . . . |
$$ . . . , O . . |
$$ . . . . . . . |[/go]

continuation:

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[go]$$B conclusion
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . X . . O . . |
$$ . . . X . O . |
$$ . . . 5 1 2 . |
$$ . 9 O 3 O . . |
$$ . . 7 4 6 . . |
$$ . . X 8 X . . |
$$ . . . . . . . |
$$ . . . , O . . |
$$ . . . . . . . |[/go]

The result is very peaceful (maybe too much so?). White is not small and has swallowed the marked stone while black has considerable thickness, but white has sente. I probably should have played at a next. Instead I wanted too much with b and got seperated while facing blacks aforementioned thickness. Won the fight with a bit of luck though...

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[go]$$W Whole board end position.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . a . . . . . . X . . O . . |
$$ | . . . O . . . . . , . . . . . X . O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . X O X O . . |
$$ | . . . . . . . . . . . . . . X O O . . |
$$ | . . b . . . . . . . . . . . X O B . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , . . . . . , . . . . . , O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . . O . O . . . . . . . X . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

What is your opinion? Is this result equal? Should white fight with a as mentioned in the 4th diagram? Are there other options for either player?

This is joseki:

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[go]$$W
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . 8 . . 4 . . 7 . . |
$$ , . . . . . X . 5 . |
$$ . . . . . . . . . . |
$$ . . . . . 3 . 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 2 . . |
$$ . . . . . . 6 . . . |
$$ . . . . . . , O . . |
$$ . . . . . . . . . . |[/go]

In the game sequence, you can resist like this:

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[go]$$B resistance
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . X . . O . . |
$$ . . . X . O . |
$$ . . . 2 1 . . |
$$ . . O . O . . |
$$ . . . . . . . |
$$ . . X . X . . |
$$ . . . . . . . |
$$ . . . , O . . |
$$ . . . . . . . |[/go]

Now, black will have two groups to deal with.

The end result from the game is simple, and doesn't look bad for either player, IMO. Given the influence, a follow-up to neutralize the influence would indeed have been better

A little side-note:

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[go]$$W
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . 2 . . 7 . . |
$$ . . . X . 3 . |
$$ . . . . c . . |
$$ . . 5 . 1 . . |
$$ . . . . . . . |
$$ . . 6 . 4 a . |
$$ . . . b . . . |
$$ . . . , W . . |
$$ . . . . . . . |[/go]

does not cut and , you can connect by attaching at 'a'. The joseki move of at 'b' does cut

That doesn't really change the way you should play in this position, but it's useful to know for evaluating the position. Even if black hadn't made the mistake of at 'c', you'd still be slightly better than joseki

Note that the connection at a implicitly offers 5 as sacrifice.

If this is the joseki you're talking about, white still has a connection at 'a' if necessary. It's not usually played, but it's there.

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[go]$$B
$$ ----------------
$$ . . . . . . . |
$$ . . . . . . . |
$$ . X . . O . . |
$$ . . . X . O . |
$$ . . . . . . . |
$$ . . O . O . . |
$$ . 5 . . . . . |
$$ . . . a X . . |
$$ . 3 . 1 . . . |
$$ . . 4 2 O . . |
$$ . . . . . . . |[/go]

Thanks for your thoughts so far. Indeed I know the joseki you showed, but I thought it only applies in case black has the marked stone already. Without this stone, after 8, white settles easily on the right while black's stones have no base. If black plays something on the right instead of 8, his stones on the top will come under severe attack while at the same time he will still need another move on the right side to completely subdue the white stone. That's why I thought black overplayed. Am I missing something?

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[go]$$W
$$ --------------------+
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . 8 . . 4 . . 7 . . |
$$ , . . . . . X . 5 . |
$$ . . . . . . . . . . |
$$ . . . . . 3 . 1 . . |
$$ . . . . . . . . . . |
$$ . . . . . . . 2 . . |
$$ . . . . . . 6 . . . |
$$ . . . . . . , O . . |
$$ . . . . . . . . . . |
$$ . . . . . . . B . . |
$$ . . . . . . . . . . |[/go]

Btw, herman I never even thought about the move you suggested. Gotta study and add it to my repertoire.

Interesting... Now that you post it, it's obvious, but I have always thought white is cut here