Rich, Consider where your control column is at the point of stall, and from there, where is the tailplane? Now, with the tailplane fully up, where is the chord line for the tailplane? Now consider the relative airflow over the tailplane which, remember, has a downforce holding the nose up.
At the point of stall, the aircraft starts to descend, an immediate change in the relative airflow occurs over the tailplane, resulting in a sudden loss of tail down force. Thus, the nose pitches down. The couple of the forces merely ensures the nose down pitch with the lift behind the weight.
An important point to remember is that incorrect loading of the aircraft causing a rearward shift in the weight can result in a severe stall that may not be recoverable.
I hope this helps with your thinking. Kevin Patterson.
