Heres a little video from the other day.
The clips when her trot is really fast, I had my leg on her and was pushing her, but basically showing her she can trot faster without breaking into a lope (as you can see she REEEEALLY wanted to do). She was a little fired up that day as well, it was really windy and other horses were galavanting around like orangutans. *le sigh*
The loping clips are in chronological order. Notice how in the first one, she picks up the wrong lead? And then after that, it got progressively better? She's quick to catch on to some ideas, and not others. April 15 - English - YouTube
I also talked to a few people who train horses this weekend, and they all had the same idea: at 4 and 5 years, horses brains tend to fall out of their ears, and they become a horse again when they are 6. LOL.