Here's a position that was played as a take/drop prop in the Bostonarea recently.
White doubles. Does Blue have a take?
Three intermediate players thought it was a drop, while two expert
playersthought it was a take. Snowie rollouts indicates that it is in
fact aneasy take. What is interesting though, was how badly the
intermediate playersmisjudged the position. They all thought it was a
not just a pass, buta big pass. But passing this position costs a
whopping .4 points,according to the rollouts. What is it about this
position that caused threedecent players to misevaluate so badly?
When one of the intermediate players was asked why she thought it
wasa pass, she said something to the effect of, "Three men on the 3
pointbehind a solid 5 prime indicates a pass. The timing of the priming
gameis very bad for Blue, that indicates a pass. If Blue gets to attack
White,he has to successfully complete the attack and then escape three
men frombehind a 5 prime, very hard to do. Everything points to
Her analysis is actually quite accurate, in a way. If Blue's only
wayto win was to win using his 3-point game, then this position would
be agood-sized pass. If Blue's only way to win was to win the priming
gameby containing White's checkers, then this position would be a
good-sizedpass. If Blue's only way to win was to attack White's checkers
as he vacatedthe 4 point, then extricating his own back checkers, then
this positionwould be a good-sized pass. What she didn't realize was
that Blue can winin any of those three ways, and he has good chances to try themall.
For example, if White rolls 6-2 and plays 21/13, Blue can attack
withtwos, threes, and fours, while escaping with sixes. If White rolls
2-2and plays 13/5, the timing of the priming game doesn't look too bad
forBlue anymore if he can roll a 6 soon. If White rolls well and safely
escapeshis three back checkers, Blue still retains significant winning
chancesthrough the racing and shot hitting chances of his three-point
game. Bluehas all these different ways to win, and he just needs one of
them to comethrough for him.
This concept comes up with ace-point and deuce-point games quite often.
ess equity in this position is about .750, which means Bluehas a pass
of White's double. It's a big pass, but not a monster one, whichmeans if
Blue has a well-timed deuce-point game and
some other decentway to win, he likely has a take.
example, from this position, Blue will likely end up with a
positionsimilar to his deuce-point game in the previous position.
However, thatis just about as bad as Blue can do, and he has another
real way to win.Over half of White's rolls fail to safety his blot, when
Blue might hitand have chances to build a counter-prime. If Blue had to
count on oneor the other of his two ways to win, he would have to pass
White's cube.But since Blue can sometimes try priming, then fall back on
his deuce-pointgame if things go badly, he can comfortably take here.
A holding game can yield two ways to win; racing, or hitting a
shot.Often times the racing chances aren't enough to take, but the shot
hittingchances compensate for this deficiency.
example, in the above position, Blue trails in the race by 15% of
theleader's pipcount, which usually indicates a pass. Blue's shot
hittingchances aren't that great, either. White will usually have two
chancesto roll a good number to cleanly clear the 10 point, and even if
Whitedoes leave a shot, Blue still has to hit it. In addition, Blue may
be forced to break his board or run with one Checker
exposing him to attack before he gets a shot. However, he definately
has some shot-hitting chances, and Blue's racing chancesalone are almost
enough for him to take. Here the shot-hitting andracing chances add up to a close take for Blue.
It is often easy to take a look at one bad aspect of a position
andconclude that it is a pass. What is more difficult is seeing several
badaspects of a position and recognizing that when put together, they
addup to a take.