Another thought: Although V1 is not a decision speed, from a practical point of view it should be a decision speed*. The monkeys up the front have just two things to do, make a decision and then action the decision. Assuming they have a healthy sense of self preservation, the actioning of the decision will be as soon as possible after the decision has been made. The monkeys don't necessarily know how long it will take between making the decision and actioning it though, and they therefore don't have the information required to know whether or not they will be taking action by V1. Far better for V1 to be the fastest speed a stop decision can be made, allowing for some standard reaction times. That way all the monkey needs to know is that if they are not at V1, they can decide to stop.
*I'm not saying the current V1 should be treated as a decision speed, I'm saying that V1 should be redefined and recalculated to be a decision speed.