I love this idea. I was actually disappointed a few years ago to see that the rules were set up the way they were, as I knew right away, it would probably be years, and years, if ever, I would want to participate in such a tournament. I wouldn't even mind if we played it like golf, and added an extra "penalty stroke" or two, even in addition to the 6 already naturally in place, to the slow speed score, just to make sure that the faster skier doesn't feel cheated.
I'm 32 years old right now, and skiing 30 mph -15 consistently. I'm loving it and having so much fun. If I can get to running 34 mph at -15 in the next year or two, my next step will be -22, not 36 mph simply because I don't want to ski at 36 mph...ever. I ski for the fun and the exercise of it, and I'm just not interested in jetting myself across the water that darn fast.
Anyway, I love the idea, and I would say it would significantly increase my chances of showing up to a tournament if this rule were implemented.