Rapid Descent
I have just watched a video of a dead-stick landing into Teterboro by a C152. The Pilot managed it quite easily by circling the airfield to reduce altitude, and was able to use any runway because of his emergency status. He seemed to be constantly flying at about 70 knots to make his glide approach. ( Vx..?)
I tried this same rapid descent scenario in a C172, and found that with full flaps and a high speed, the height came off quite rapidly. (about 2000ft/min.) I limited the speed to just below Vf as I didn't want to exceed that. Once the height was suitable then I could continue with the slower 65-70 knots approach speed, but this only made -600ft/min., as it is closer to the minimum part of the drag curve.
I was never taught this manoeuvre, but it could be useful one day.