Spoony

Everyone I know who manually shifts an automatic tranny does for bullshit reasons like neutral drops, or for performance, starting in 1 going to redline then moving to 2, this sort of activity does put extra strain on an auto, and will eventually cause problems. Standard transmissions are generally tougher then automatics and will take more abuse (until you start talking about very expensive auto's) I think this is part of the reason people associate shifting an auto with damaging it, if you do it properly you shouldn't really cause any damage.

That being said I agree with DC52NV, shifting an auto just for the sake of doing so is rather asinine, and totally defeats the point of the auto being there in the first place. If you want to shift "like a standard" your best bet is to make sure you get one in the first place.