Do I ever stand up?
I've noticed that after holding down kick for a while I stop kicking, does the same happen to ducking, as far as I can tell it doesn't.
Also are there any other reasons not to hold down duck all the time? (apart from sore fingers) Such as it interrupting other moves.
As you can see in this Rage Perspective
it doesn't seem to stop. I also tested it myself, you can even hold down while jumping and trampolining.