Never flew a Q400 but if its anything like the CRJ the pusher is designed for a high-altitude stall recovery. At low altitude if you over ride it with the AP/SP disconnect switch and hold it in you can actually use the little bit of Alpha margin left to recover from a stall. Its not something trained but I did it in the sim years ago. If you actually try to recover low altitude (with the pusher activated) without pushing and holding the AP/SP button you will not recover before hitting the ground. Any Q400 pilot's chime in.....or maybe give it a shot in the sim. Please no self proclaimed performance experts....