Funny thing is, they don't make rigid motocross bikes so people learn "correctly". They make slower ones with lesser suspension, but no one forces anyone to start on those, either.I actually agree with this, wholeheartedly in fact.
One of the points I was making earlier, and perhaps I did not spell it out well enough is that a big travel bike allows for the rider to make all kinds of basic mistakes - poor line choice, sloppy technique - which, when you combine them with the speeds a big bike allows means big injuries.
This guy's already probably got the basics from riding motocross anyway. I took a 45 year old with me last weekend for his first time riding lifts (on a borrowed fsr xc) and his motorcycle (trails mostly) background helped him to get down the mountain in one piece, and actually at a pretty good pace, especially considering the equipment he had.