Im saying that with a 6:35 arrival for a 7 am opening we did not wait more than 20 minutes for anything (including Mine Train, Splash, Thunder, Space, Pirates) but again we left right after lunch. Did people there on the same day wait more than 20 minutes, absolutely. Can it be done with minimal waits if you arrive early enough, absolutely.
If you catch a 7 am opening, most people won't get there that early and alot of success can be had.
Fantasyland about 10 am on Thanksgiving Day
Main Street - mid morning (not sure of what time) - lots of room there.