I too looked at this and initially saw plenty of play remaining and a racing lead.
The opponent's position and the likelihood of getting primed is surely a major problem, but is not what makes this a monster drop. That is due to the major flaw in yellow's position - the fact that the midpoint is gone. Its value here in connecting the rear checkers and covering the outfield is huge. The racing lead is totally misleading. Yellow would be far better off down 10 pips than up 10 pips to get the midpoint back.
What's that midpoint worth? I did a very short rollout here on my dinosaur laptop. Whether it is a small take or a small pass is not so important. What is obvious either way is how moving 20 pips backwards to reestablish the midpoint and provide some extra timing is worth the cost of a whopping burger and fries lunch - 0.300
 is Player 2score: 0 pip: 158 | ||||||||||||||||
 | 11 point match | |||||||||||||||
| pip: 164 score: 0  is Player 1 | ||||||||||||||||
| XGID=-a--BbCBB---cC--ab-bbb-C--:0:0:-1:00:0:0:0:11:10 | ||||||||||||||||
| on roll, cube action? | ||||||||||||||||
| Analyzed in Rollout | |
| No Double | |
| Player Winning Chances: | 71.30% (G: 21.31% B: 1.25%) |
| Opponent Winning Chances: | 28.70% (G: 5.86% B: 0.25%) |
| Double/Take | |
| Player Winning Chances: | 70.81% (G: 22.36% B: 1.56%) |
| Opponent Winning Chances: | 29.19% (G: 5.88% B: 0.19%) |
| Cubeless Equities | |
| No Double: | +0.594 |
| Double: | +1.215 |
| Cubeful Equities | |
| No Double: | +0.892 (-0.096) |
| Double/Take: | +0.987 |
| Double/Drop: | +1.000 (+0.013) |
| Best Cube action: Double / Take | |
| Rollout details | |
| 334 Games rolled with Variance Reduction. Moves and cube decisions: 3 ply | |
| Confidence No Double: | ± 0.028 (+0.864...+0.920) |
| Confidence Double: | ± 0.053 (+0.935...+1.040) |
| Double Decision confidence: | 99.9% |
| Take Decision confidence: | 68.0% |
| Duration: 50 minutes 34 seconds | |
eXtreme Gammon Version: 1.21, MET: Rockwell-Kazaross