As for spinning, if you only teach someone incipient spinning and he tries it on his own and the aircraft does not recover, would it not have been a good idea to show him how to get out of a fully developed spin? A little knowledge is a dangerous thing!
You would have to be pretty wreckless to practice incipient spins if you have not been trained to recover!
Mentioned elsewhere I think, but more pilots are killed practising spins than befalling inadvertent spins.
Each to their own, but this thread has the general air that spinning is a normal activity that we should all endeavour to excersise and that we are incomplete pilots if we don't - tosh!. Inexperienced pilots should not feel comfortable putting their aircraft into a spin just in case it may happen for real.
My guess is that spinning has little to do with generall all round safe and efficient PPL skills.