Stochastic impact analysis gives wrong results

Playing with these MoveAdjustments for Robot1.M in tutorial gives this stochastic impact result:

According to the shown analysis, A1, A2, and A4 of the Second MoveRobot activity are not always on the critical path. However, in practice, they should consistently appear on the critical path with these settings.

An analysis of this issue reveals that it is caused by minor rounding errors. On the left, you can see the correct output, while on the right, the rounding discrepancies lead to the unexpected behavior.