I imagine an addon that displays something while holding a key down and stops displaying it when released. (like holding shift while highlighting a piece of gear showing whats currently equipped in that slot and stat comparisons)

That would probably be a very simple and built in use for that API. That is funny that a blue stated one keypress UP & Down to be a 'wow keypress'. Funny how blues seem to contradict each other a lot. There must be zero written rules about these topics at blizzard HQ. It's all a blues 'interpretation' of the ToS just like ours.