Hello!



White is leading 2-0 in a 5 point match. Green doubles. White drops. This is criticized as massive blunder.

I don't really understand why. Green has a lead of 16 in the pipcount. Green has hitting opportunities. (White has also hitting opportunities but probably less after Greens move.) White has to be afraid of a gammon because it has no anchor. White is leading in the score. Summary: Pipcount, hitting opportunities, gammon threat and score all argue for a drop.

How would you come to the decision here that it's a clear take?

Green has only has 9 men in the zone, which stinks. Even board strength.

For $, this is not even a double...

White has a lot of play here. Green has threats, but he isn’t going to be able to actually do all of them. His 5s are duplicated (cover ace or hit loose on 3?) He doesn’t have much ammo for a blitz, and it’s likely that white will end up anchoring on the 3 or 5. Worst case: green fails to cover the ace blot, white rolls a 51, 41 or 31. All of a sudden green is the one looking at a possible blitz. On second look, 55 would be even better - white hits two, makes the ace point and anchors on the 5 — green is in serious trouble!!

In a game this close to being turned around, it is hard to fathom that white would not have a take. Even just making one of the anchors would make it a much more even game.

That's for sure! Just rolled this out and after D/T White hits in 77.25%!! of games (much more than I'd have guessed). Green hits in 96.4% of games.
So mucho play left here (most of the time), and that 16 point race lead does not mean much.

The best way to understand a position like this is to set it up on a board and play it out a few dozen times. You'll quickly understand that Green has a lot more problems bringing this home than you think.

The last two answers involve rollouts which I can't do during a match. I indeed made some and saw White losing most of the time and winning only under unreal circumstances like Green hitting nothing at all + White doublehitting or White falling down to 10% winning chances only to make an unbelievable turn around 20 moves after that cube decision.

I would rather need a rule of the form: Don't drop when A and B or C unless D or something like that.

I find the PRAT rule a helpful guide (but certainly not infallible). It stands for position, race and threats. Basically it says if you have a significant advantage in two of these three you should double, and if you have a significant advantage in all three your opponent should drop. In the given position, race certainly favors green, threats slightly favor green (white has threats of his own to counter green’s) and position is about even. The even position argues for a take by white. The threats and race argue for a double by green (as does the match score) but I suspect it is closer to no double than it is to double/pass.

I am a fan of PRAT too. I saw it like this: Race and threats are on the side of Green which makes it a double. The take would be normally decided by the position. But this third judge is silent. So we have to look at other (smaller) criteria to decide this. The "minor judges" score and gammon risk both point to a drop.

My problem with PRAT is that there are small and big racing leads/position advantages/threats. Do you know some kind of "points system" that quantifies those? Or any other system that helps with such tricky cube decisions?

There are no such rules. The point of doing rollouts is to develop a general understanding of how positions develop and how easily apparent advantages can slip away, especially when you don't have many crushing threats and your opponent has a good board. In backgammon, 'unbelievable turnarounds' aren't all that uncommon or unbelievable.