I think it's more that the value network includes moves which look plausible but won't concentrate around the answer to a forcing move as having >99% probabilit

I think it's more that the value network includes moves which look plausible but won't concentrate around the answer to a forcing move as having >99% probability. A human has a heuristic: "I must play here else I lose" but AG assumes its opponent might play anywhere that the ANN calls reasonable.