You want reasons why?
Because...
If this is a Player given option, then it is simply one more thing for coordinators to attempt to convince dot-builders to coordinate and match with their teammates, dot-builders to predominantly refuse, and potentially lower the ability of a coordinator to accurately predict when and where to use which players.
If this is a Coordinator granted option, then it is simply a way for a coordinator to mute the addition of stamina to a dot by forcing him to take unneeded plays off.
Simply put I don't like changing pretty much anything that would potentially further complicate the "Tactics" post I seem to be making all too regularly.