I ride wide for comfort and comtrol (2.4) training on heavier alloy wheels. More thsn happy with my new ardent race 2.25s though for race day. More than enough traction and fast. Advantage with wider tires is lower pressure. I read an article though that said for every extra pound you carry a mile uphill you will lose 20 seconds on average so with all the climbing at mooch I'd say skinny would gain the most time in the end and even more so if you ride full squish. And that test was on a straight 1 mile road hill. I'm sure it would multiply in technical, rocky terrain.