my primary app through AACOMAs took forever to complete and wasn't sent to my schools until the beginning of january. about two weeks later i was called to interview at their campus...they actually wanted me to come a week and a half later! i was a bit confused since i never received any formal request for a secondary. i was then told over the phone to just complete it as soon as possible.
so it is possible, though i don't think it's very common. i'm attributing it to the fact that i'm out of state...i guess so i don't get my hopes up too high!