Kuolema: After 1, black must play at 2 to to prevent snapback. Then white wins the semeai.
unkx80: Not wrong -- but presentation could be improved.
(1) I expect a variation when is played at...
(2) What's up with and
?
and W has two eyes. It's more reasonable play by B, instead of giving up all the stones.
Bill: This is slightly better for White.
EricBackus: OK, it's obvious to me now. But I initially thought that was a sub-optimal solution, similar to the correct solution posted above. Of course, it's really a failure, because of
at a, which lets black live and white die.