So, have I got this right...?
Icing on tail plane
1. Normal approach. No flap. As airspeed slows, tail plane stalls prematurely. Elevator ineffective. Tail goes up, nose goes down. Aeroplane also goes rapidly down.
Other possibility ...
2. Normal approach. Extend flaps (C172 or C150). Centre of lift goes back. Nose goes down. Tail plane angle of incidence increases. Tail plane stalls. Result as above.
SD