Quarry Ridge was pretty rutted up and loose last night before I groomed. The uphills were pretty ripped up from bikes, especially in the corners and steeper sections. The tracked machine packed it right down. You need pressure to pack snow (just like a snowmobile or CC ski drag). For bikes, you need the trail compacted to several psi, much higher than you need for skis. That's why the snowshoes work so well since they are close to the compaction of a bike tire.