They probably needed heavier weights to get the rpm. down, so it wouldn't suck so much gas. On a flat hard track you don't need an optimal clutching set up to achieve high speeds.
I drove my sled from Sheboygan wi. To copper harbor in 13 hours with no preparations no support team stopped for gas lunch and beer and drove the last 100 mi. In a snow storm. Back and forth wide open on a closed course..not impressed
I'm from Lakewood wi. I went outside today, a quarter in of snow fell last night on top of the one inch of snow I got out of the big storm. Trails remain good to very good as they have been all season.