For a little perspective, a guy I know (late 30s) recently competed in a triathalon (shortened to a biathlon because of rough ocean conditions) and won the corporate division. The bike portion was 40K or just under 25 miles. He did it in just under a hour. When we speak of the speed pros ride at, we must remember the huge drafting advantage from riding in the peleton. Even breakaways typically have a few riders sharing the load. And these guys are able to maximize drafting by riding very close together. I think most recreational riders can't do that even when they ride with a group.

my .02