John's play of playing safe seems perfectly reasonable as we're decently ahead in the race, outboarded, out offensive positioned, and we have a play that could leave zero blots instead of leaving four! So why does XG hate it so?
If we have a look at the position after playing 6, 8 it's obviously wildly inflexible. We will have a real tough time coming up with numbers that play cleanly in our upcoming turns. The six point is over stacked and the rest of our points are basically stripped out. This means at some point we will likely have to take some calculated risks. XG says that time is now. Again, why?
We have the opportunity now to attack and get something going. If we wait a turn we won't likely have the dice to attack. (and there likely won't be much to attack anyway as we'll allow our opponent to anchor up or run to a more secure position) By double hitting we unstack while putting two on the bar and keep our position fluid. We have eleven men in the zone and the most advanced anchor available to us so there are definitely some factors pointing to going for the throat.
Often times I feel people don't envision what will happen over the next couple rolls well even when it's fairly straightforward. That is, after all, why XG is so much better than us plebeians. The bot is able to look into the future and weigh all the potential outcomes and spit out what's best overall. Here if we hit there's the obvious massive downside, the opponent rolls a five. (or to a lesser extent double twos or double fours) Barring that though we're doing rather well or moderately well on the numbers where he fans or only comes in with one not hitting and when he hits on the ace we still have a shake to come in good ourselves.
The problem with playing safe is there is no upside. After every last one of the opp's rolls we're just losing to varying degrees. At least with the double hit there is a non negligible chance at seeing some sunshine on an otherwise cloudy day.
Another thing worth mentioning that I really didn't look into but feel is true...the double hit will lead to inefficient cubes for the opponent when things do go well. He can't cube now so when he does it's likely to be a stone cold not going to lose any sleep over it pass.
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| XGID=-aaB-aE-BA-AcB----bcbbB---:0:0:1:15:0:0:3:0:10 | |||||
| Blue to play 15 | |||||
| 1. | Rollout1 | 6/1* 6/5* | eq: -0.344 | |||
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| 2. | Rollout1 | 11/6 9/8 | eq: -0.455 (-0.111) | |||
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| 1 648 Games rolled with Variance Reduction. Dice Seed: 76564279 Moves: 3-ply, cube decisions: XG Roller | ||||||