the dorbel daily

Sunday 1 May 2011

The Big Quiz, part 5



White leads 1-0 to 5 with Blue to play 6-4. The sharp play here is 8/2, 6/2, ever so slightly better than 24/14 or 24/18, 13/9. It wins an extra gammon or two but more importantly, it often leads to exactly the sort of position with gammonish threats where the match trailer can turn the cube with some freedom. It's interesting to see why it does this. Blue wants to seek out positions where he can attack, or even threaten to attack, White's back men when they split. White will want to split fairly early to try for the high anchor that she needs in order to avert gammon threats and when Blue makes his 2pt, he stops White from making the safest split which is 24/23. This gives White some awkward ones to play in the early part of the game. Cute eh? 1 point for this modern play and nothing for the others, even though they are only very slightly inferior.

I made this play in the match, so the game goes like this.
Blue 6-4, 8/2, 6/2
White 4-2, 8/4, 6/4
Blue 6-5, 24/13
White 3-1, 8/5, 6/5
Blue 5-5, 13/3(2)
White 3-1, 13/10, 8/7
(13/9 is better, or 13/10, 6/5. Note how White can't even think about splitting at the back or Blue will cube)
Blue 5-2...........
How do you tackle this one?



We'll look at the best play tomorrow, until then, keep posting comments please and above all, enjoy the game!

5 comments:

RickrInSF said...

well, first thing ya gotta do is count the damn pips
another 10 min of my time, gone in a mental exercise

kamikaze said...

i cant really pip count yet, but i think blue is ahead by a reasonable amount. from our lesson the other day, (when ahead in the race, race) i guess blue should run (24/17).

but i am still tempted by my older, more conservative ways: 24/22 to the edge of the prime, and 13/8 attacking any of my opponents escapees with an extra builder.

for this quiz i will totally ignore the recent good advice and go with 24/22 13/8 :)

--kamikaze

ah_clem said...

Blue really wants to get his runner out of there before White's prime gets any bigger. He can either run outright, or step up to the edge by playing 24/22. Running exposes blue to a double shot and White will gladly hit loose - staying on the 22 still gives a double shot, but there are real consequences for hitting loose and only 34, 11 or 22 POH. So I like playing to the 22 better than running. Plus, bringing a spare to the eight point can't hurt our game.

I thought about the aggressive D (13/8 13/11) which brings two builders into range to build the prime, but extricating the runner seems to be the more immediate problem.

24/22 13/8 Note that the runner is i UTG on the 22 - move the builder on the 15 to the 16 and it's a different story.

ah_clem said...

re pip counting: You don't need to do an explicit pip count to see that blue is way ahead. Blue has escaped a runner while white still has two back. Midpoints are even and the outfield is almost even. Blue is a bit ahead in his inner board ( good for the race, bad for strategy.)

Credit Blue with 18 pips for moving a runner from the 24 to the 6, another 8 for his homeboard men and one for the outfield and you get a 27 pip lead. This may be off by a bit, but it's close enough for the decision we have to make.

ah_clem said...

Blue really wants to get his runner out of there before White's prime gets any bigger. He can either run outright, or step up to the edge by playing 24/22. Running exposes blue to a double shot and White will gladly hit loose - staying on the 22 still gives a double shot, but there are real consequences for hitting loose and only 34, 11 or 22 POH. So I like playing to the 22 better than running. Plus, bringing a spare to the eight point can't hurt our game.

I thought about the aggressive D (13/8 13/11) which brings two builders into range to build the prime, but extricating the runner seems to be the more immediate problem.

24/22 13/8 Note that the runner is i UTG on the 22 - move the builder on the 15 to the 16 and it's a different story.