1) When each skier signs up, they indicate their opening pass. (One downside of this idea is that I think they'll be forced to stick to that.)
2) Group skiers based on opening pass. For example, just order them from easiest opener to hardest opener.
It's not perfect, but it's so simple that maybe it's worth trying.
Background: We've just resumed summer pole vault meets. In that sport (and also high jump), everyone in the competition who wants to attempt a certain height has to do it while the bar is at that height. The bar never goes back down.
So it's very natural that the way to organize some groups just for practical purposes is by opening height.
However, a consequence of this is that vaulters of similar skill level are participating in the competition at the same time, without making any direct attempt to group by ability.
This is cool for me personally (well, when my knee isn't injured...) because there is no other obvious "division" where I'd be against anybody at a similar level. In "old guys," I'd be competing with folks who have vaulted their entire lives and are far better than I am. Younger males start out much worse than I am for a while, but when they start to get it, they rocket past me.
BUT the best high school girls are right around my level. So this grouping by opening height let's me see if I can beat some of them on that day. And certain of them seem very motivated to beat an old man (though others don't care at all).
Does it make sense for slalom? Not sure. But does create ability groups without much effort.
Nathaniel Bogan -- GUT Padawan