I think close to the factory would be tough, finding land to do it isn't really that practical. And while the proving grounds might be possible, they're not really that convenient for people that might be flying in from somewhere. Don't get me wrong, I think the idea in general is a good one, I just think it might be logistically a little tough. SE Michigan isn't exactly on anyone's long list of great places to do any off-roading
A number of years back Jeep had an event that I think they did in several locations that I think would be something that would be a good idea to bring back. I can't remember exactly what they called it, but they basically had a weekend where they had things set up so you could participate in several things - they had a small off-road track that you could drive one of several different jeep vehicles through with a rep guiding you. They were doing test drives of vehicles on the regular roads, and then they also had a small off-road area that was set up so that if you owned a jeep they allowed you to drive the off-road section. It wasn't anything extreme, but it was something that would at least let people get an idea of off-road driving without getting themselves into too much trouble.