I don't think any of the robo-tractors can transport on the road yet. So, you combine a 40A field in 2 hrs & move 2 miles to another field. Who in the operation that is doing nothing can come get the cart (assuming it still has a cab) and drive it 10 minutes to the next field?

As I've said many times, this is a waste of time. I'm not sure why people can't find careful & competent cart drivers. Especially when you factor in the increased cost of the robo-tractor. Will this be a dedicated tractor? Or, the same one you plant, spray, sidedress, and till with? Probably not. No, truck drivers are not going to load their own trucks. Actually, there's no time for that unless you have lots of trucks and low performing corn/beans.

In this part of the country, with decent yields and normal & matching size equipment, the cart is on a dead run most of the time. About the only wait time for a cart is when the combine is breaking through on a new land, but the hi-speed action is soon to get underway again.