Stam,
I agree with you about the fishing start times if you are fishing the East Cape area beaches.
Medano beach is a different animal. It can be a cluster once everyone's hangover wears off and they start hitting the beach and watercrafts, especially if you are flyfishing.
Trying to avoid hitting the beach walkers with your backcast or the dude trying to sell you hats, necklaces etc can be interesting.
Plus I'm generally ready for a beer or margarita by 10:00....