I suspect the wait command over-rides the queueing that you'd get if you pressed the keys manually. When you think about it, when you queue abilities up, the game is effectively inserting a wait instruction anyway. The macro is simply emulating what the game already does, and it's probably similar if not identical code at the back-end.

So the answer really is that you have a choice. Do you want the efficiency of manually queueing up actions, or do you want the convenience of having the game do it for you?