Since no one replied to my post on the Austrian Tri team regarding this issue, I'll ask the question. It is not behavior that I see among road bikers, but perhaps its "de rigueur" for Triathletes?

I noticed that they leave their shoes on the bike. Before a ride the mount the bike, and put thier foot in one shoe, unclip, and put on the other shoe, Now this may be standard for triathletes, but since I'm not one, so it was strange to me.