Okay, I'm being somewhat facetious, but I've just never had problems with blisters. Not when I used to carry a heavy pack and wear full leather Danners with Goretex; not now, with a light pack and trail runners. Wet feet from stream crossings cause no problems. I've never done anything very special--at this point, I carry moleskin out of habit, and should probably get rid of it.
Do some people's feet have a greater tendency to blister, regardless of conditioning, footwear, etc? I'm introducing a couple friends to backpacking--I'd hate for them to suffer with blisters just because I don't think prevention is very complicated (or, in my case apparently, even necessary). Are there certain foot/body types more vulnerable to blistering? Things to look out for (other than ill-fitting shoes and hotspots)?
Sorry if this is a bit of a thread drift, but I'd hate to tell a friend stream-wading will be just fine, if it only works for some people's feet.