(1) There is a certain amount of parsing and processing overhead.
(2) Yes, if you try and run at very high speeds without acceleration, you can cause it to fail.
There aren’t any rules here. Outside of the AxiDraw software, you can easily enter raw movement commands that are faster than the AxiDraw itself can move or accelerate. This shouldn’t be surprising.
It *may* work, but we don’t test with these kinds of parameters, nor guarantee it to work there. (We also don’t guarantee that you can’t cause physical damage to the machine by testing the limits in this way.)