I am not sure how to implement this at the moment but I woud think that there might be a way for someone to send to many inputs at one time. Not implicelty cheating, but this could create some kind of lag spike so the best way I can think of this is just make sure that the action isnt pressed more than 20 times a second. That would probably be better handled when doing the logic for the action itself but I suppose you could also make a bool and return early if the game detects too many inputs at once.
Inputs are sent at the approximate frame rate of the user so someone running at 120fps will actually send 120 inputs a second.
Sending inputs twice each time might be a way of bypassing this. Using the time could them be used as a form of unique marker to ensure inputs are not duplicated.