Glen, you must be having a mental block on this. A heavy flywheel acts just like the
friction toys we had as kids. You know, you would "rev them up" by moving them along the ground rapidly, then place them on the ground and they would zoom away on their own. But, if you placed your friction toy race car at the top of the hill and let gravity take it down, it would lose to every other toy car that was not a friction car (and sometimes it wouldn't even go down the hill without being revved up first). That is the difference between a light flywheel and a heavy flyweel.
