Underpromotion percentage

[Uri Blass]

<snipped>

I am only interested in promotions where the promotion piece is not taken on the next move. It should be easy to filter out these automatically.

it means that the following underpromotion is not interesting for you
inspite of the fact that it is the only saving move for white.

[d]rr6/k1P5/P7/K7/8/1q6/8/8 w - - 0 1 bm c8N

Uri

[Uri Blass]

But you also need a good engine. Junior outbooked Rybka in the last tourney and had a won game, then blew it up, if Hiarcs, Sjeng or another engine played that opening against Rybka it would have been perhaps a win against Rybka. Book wins aren't easy against her.

Junior did not outbook Rybka.
Rybka's blunder was when she was out of book.

Junior took advantage of weaknesses in the rybka's engine to get a better position.

Uri

[Uri Blass]

I can add that based on what I read Junior did not leave book at winning position and simply came out of book in position that it knew to play better.

Uri