Your right, I didn't get that from what you originally wrote. But that
defeats the whole purpose of ventilation, doesn't it? The purpose it to
ensure use year round. But I have to admit, you are correct. If you don't
use the fan, not much moisture will get trapped in the attic.

You entirely missed what I wrote. The whole idea is NOT to dump
moisture into the attic by NOT running the fan during cool outside
conditions.