would posit that the way spin training would have avoided MOST of the accidents is by teaching pilots what happens when you:
1) Start a tight turn at a low airspeed
2) Add a bit of rudder to speed up the turn
3) Notice that you are banking a bit more than you'd like to and add some opposite aileron to "flatten the turn"
4) Notice that the nose seems to be falling and add elevator.
All of which are taught in spin avoidance..........