I think the question as to whether an MD CAN be trained to do a spay/neuter has been answered. Of course they can. As mentioned before, you can train a monkey or a vet student--or an MD--regardless of their surgical experience.
I think the question I've been trying to answer is more "SHOULD an MD be trained to spay/neuter?" Greg, nobody is questioning your surgical acumen. However, just because you--or an MD, or a person off the street--CAN be trained to spay/neuter, SHOULD they?
My board-certified surgeon friends crack the chests of dogs and cats all the time, and perform craniotomies to boot. CAN they be trained to do surgeries on humans? Sure. However, I doubt that anyone would argue that they SHOULD. The same principle holds true for MDs and veterinary surgeries. And, yes, it's arrogant to think that it only works one way.
(and btw, I agree that the example I cited above regarding the ureters constitutes malmpractice--it was brought up to illustrate the point that straightforward procedures can be complex if not approached seriously.)