One other thing -- I'm not sure I'd want to characterize clipping out on the same side each time as a "bad habit", ESPECIALLY for people new to clipless. I think when you're first starting to use clipless pedals, unless you're super coordinated (which some people are!), it takes a while to get establish the muscle memory/neural pathway/whatever to automatically clip out when you need to stop, and to lean to the correct side. Having a pattern that your conscious brain can hang on to -- "slow down, clip out left, lean left, stop" -- can really make this process faster and easier.

I've been riding with clipless pedals for about a year and a half, and I don't think about my pedals anymore. I DO clip out on the same side 90% of the time, not because of some rigid adherence to habit, but because I get a faster start with my dominant leg clipped in. However, I've demonstrated to myself a few times recently that when I NEED to clip out on the other side (such as when I'm going 2mph in deep sand and start to lose it), I have no trouble doing it, and I don't have to think about it, and I don't risk leaning to the wrong side --it's just as automatic as my "sweet" side.