Thanks for the update on Nevada's progress. Yes, you are right to keep it slow. You don't want to blow his poor little mind. In fact, I recently read an interesting article in Equus, which is here:
http://equusmagazine.com/content/content/12254/threeminutehorsemanship.pdf
One thing the article says, which I found out long ago when training Penny: "I then researched this idea and found that in an experiment carried out in 1980 by a scientist called Rubin, ponies were trained in short sessions for either seven days, two days or one day a week. The results were surprising: The ponies who were trained for only one day a week achieved a higher level of performance in fewer training sessions." I always wondered why this was, and then I heard something on the public radio station I often listen to about how rats who ran a maze and then napped afterward dreamed they were running the maze, i.e., practicing in their sleep. If rats do it, why not horses? I found that the best formula was one day of a short training session (about a half hour), then a day or 2 off before the next one. Often, what she wouldn't quite get in one session, she knew like she'd known it all along in the next one. It was as if she'd been doing her homework! But I couldn't believe a horse, while hanging out in the field, grazing, is thinking about the last training session and figuring it out. So what was going on? I never had an answer till that radio show about the rats. Here's a quick recap of what the scientists at MIT are studying:
Perchance to Dream
A DUSTING ? ? ? 
Right ? ? ? 
