First off, do whatever feels right to YOU. He's not the one riding the bike.

I'd say he's never ridden a compact crankset. On my compact, I'm often in the big ring, and only use the small ring when there are significant climbs. It's pretty flat where I am, and so I'm often in the big ring for the entire ride.

On my bike with a regular triple, I'm more often in the middle ring, and sometimes in the big ring.

But really, you should do whatever is best for you.