I have.
It's really fun to watch
two of them operate in tandem in between trees. And you thought parallel parking was hard.
I'm trying to find information on a groomer design that was supposed to groom moguls. Here is the patent, to a guy who was head of snowmaking at Hunter Mountain for a while.
mountain:
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I'd love to get a real-life pic of that thing. There is supposed to be a 4-piece tiller somewhere up there, I don't think that's it though.