For part of the FAA CPLs we did all manner of accelerated stalls etc....My best stall was upside down at the top of a loop and we ended up falling with style. It was quite surreal, I can still remember watching the car on the road that we'd been using as a reference line 5000' below as the harness straps were fluttering around my ears and we were weightless, with an aero's FI laughling like a hyena beside me....I was a bit overloaded then and forgot to close the throttle so we were accelerating downward and a remarkable rate of knots. After what seemed like an eternity (probably a couple of seconds) he said "my plane" and recovered from my numerous botched recoveries in which I stalled about 10 times ( felt like it anyway).
Regarding taking over - Depends. I have taken over in the past when the person I used to fly with (in a shared aeroplane of which I owned a share) was destined to break the aeroplane on landing after flaring at about 50 feet and just waiting for the inevitable. Now I'd certainly take over if we were about to die horribly and I knew I could save us - self preservation and all that.
800'....our circuit is 800'....