A miniature horse is just that …a horse in miniature. In general, they are a lot more sensible than big horses which enables them to learn a little quicker. The flight instinct is not triggered as easily in my experience, but it is definately still there.
It’s probably best if the client hooks up with a trainer who is experienced with these little guys. There is a need to be familiar with how to feed them, how much can be asked in training and how much can be asked when driving them and of course, you need the same equipment, but it has to be the right size. That equipment is very available if you know where to look.
They learn very quickly, but the handler has to make sure that the lessons are solid before moving on. It is tempting to rush the process with a miniature. You have to have a feel for how solid they are in each step.
I have trained many, many minis to drive. Like everything else, it’s easy when you know how, but if you don’t know how, then I’d advise that you not take it on. Believe me when I tell you that a runaway mini with a cart behind it can be just as frightening and dangerous and unstoppable as any other runaway equine. The training must be in place to prevent, as best we can, any such event.
Training a mini to drive is far easier than teaching a 16 hand horse to drive, but the basic process is the same, just as the equipment used is the same. The small horse must learn the same things, in the same way, as the big horses and the end result must be an educated, reasonably safe (or as safe as a driving horse can be) horse for almost anyone to drive.
Miniature driving horses and their owners are very active in the combined driving world as well as the breed ring. They can learn dressage, just as their bigger cousins. They can learn to be on the bit, collect, extend, back up, etc.
Miniature horse driving is the same as any other horse driving. It’s just down-sized.