Honestly, a taser is a weapon, you better be able to use it properly before shooting somone with it; myself, it would stop my heart, no kidding. I can't see any officer not seeking martial training as an incentive to using a weapon.
I don't care how irate a person gets, a tazer should be employed after you have failed to calm or restrain the individual(and no less); even then it should be treated as a dangorous weapon; the only situation in which it should be used is when you are at risk, even then officers have guns and understand the risk in using them, or so I hope, tasers need the same attention.