I finally hooked Topper and rode behind him in the cart. There was some head tossing, we think because he wanted to go and I wanted to walk, but he was good and I was able to easily control him with my header there just in case. We're learning to communicate for the tighter turns, where he has to cross over and I don't think it'll be that long before I'll be comfortable without the header. I've hooked alone already, and he's been great about standing for it all. He's Amish, so we figure he's driven, but we've taken our time, because when we introduced the idea of the shafts he was the opposite of calm. Now he handles it all without acting nervous, but sometimes he can be impatient to go. I'm rather excited about all this.
Here's a video
https://youtu.be/AiDJDvz4YSw