I really wish my avatar could tell the difference between an attack and a DoT. I've lost count of the times I put my weapons away only to pull them out again simply because of a damage effect. Even if the non-combat restoration rates can't kick in until the DoT fades it would be much nicer not to feel like I'm arguing with myself.
I'd very much like to be able to turn off the auto-defense as well. However, I'll suggest @Cobra101 to change the title of your thread to something more in line with the actual request.
Needs to be turned off on purpose by advanced players. New players will flail around trying to remember how to draw their weapons.