This is another one of those situations where there's a default (5pt) for the vast majority of positions and another play (4pt) where you have to search hard to have an excuse to make that play correct. I thought the 4pt had some merit here OtB given that making the 5pt leaves so many shots also leaving two blots and really the only thing the opponent has going for him is an okay board.
Turns out the 5pt is the 5pt is the 5pt. XGR++ had the 5pt correct by only .004 so the rollout cleared things up a bit. CMC said since we had a high anchor we need not be worried about the lots of shots and that may not be the right way to think about it. We are more likely to make the 5pt if we have a worse anchor. Note in the variants I have tossed the spare to the midpoint which makes the race and our ability to blockade offensively much better.

              
 
              
 | | White is Player 2
score: 0 pip: 140 | Unlimited Game Jacoby Beaver | pip: 161 score: 0
Blue is Player 1 | |
| XGID=-a--AaD-C-B-dB---c-b-Cb-b-:0:0:1:51:0:0:3:0:10 |
| Blue to play 51 |
| 1. | Rollout1 | 10/5* 6/5 | eq: +0.301 |
| Player: Opponent: | 57.38% (G:18.89% B:0.77%) 42.62% (G:15.30% B:0.37%) | Conf.: ± 0.011 (+0.291...+0.312) - [100.0%] Duration: 1 minute 39 seconds |
|
| 2. | Rollout1 | 10/5* 5/4 | eq: +0.261 (-0.040) |
| Player: Opponent: | 55.85% (G:18.70% B:0.61%) 44.15% (G:11.63% B:0.32%) | Conf.: ± 0.010 (+0.251...+0.271) - [0.0%] Duration: 1 minute 34 seconds |
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| |
1 2592 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
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Variant 1
Interesting that 3 ply made the wrong play. + and ++ got it right.

              
 
              
 | | White is Player 2
score: 0 pip: 140 | Unlimited Game Jacoby Beaver | pip: 151 score: 0
Blue is Player 1 | |
| XGID=-a--AaD-C-B-dC---c-bB-b-b-:0:0:1:51:0:0:3:0:10 |
| Blue to play 51 |
| 1. | Rollout1 | 10/5* 5/4 | eq: +0.518 |
| Player: Opponent: | 61.86% (G:19.14% B:0.60%) 38.14% (G:7.88% B:0.20%) | Conf.: ± 0.012 (+0.506...+0.530) - [100.0%] Duration: 53.1 seconds |
|
| 2. | Rollout1 | 10/5* 6/5 | eq: +0.479 (-0.039) |
| Player: Opponent: | 60.67% (G:19.04% B:0.62%) 39.33% (G:10.52% B:0.22%) | Conf.: ± 0.016 (+0.463...+0.495) - [0.0%] Duration: 53.3 seconds |
|
| |
1 1296 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
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Variant 2

              
 
              
 | | White is Player 2
score: 0 pip: 140 | Unlimited Game Jacoby Beaver | pip: 157 score: 0
Blue is Player 1 | |
| XGID=-a--AaD-C-B-dC---c-b--bBb-:0:0:1:51:0:0:3:0:10 |
| Blue to play 51 |
| 1. | Rollout1 | 10/5* 6/5 | eq: +0.281 |
| Player: Opponent: | 57.26% (G:19.31% B:0.81%) 42.74% (G:15.99% B:0.70%) | Conf.: ± 0.009 (+0.272...+0.290) - [100.0%] Duration: 3 minutes 09 seconds |
|
| 2. | Rollout1 | 10/5* 5/4 | eq: +0.237 (-0.043) |
| Player: Opponent: | 55.28% (G:19.73% B:0.72%) 44.72% (G:13.62% B:0.54%) | Conf.: ± 0.012 (+0.225...+0.249) - [0.0%] Duration: 2 minutes 56 seconds |
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| |
1 5184 Games rolled with Variance Reduction. Moves: 3-ply, cube decisions: XG Roller
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