So, a few days ago he took me out to a rarely traveled stretch of road in the park, set out orange cones for me to use in spotting my position, climbed down from the drivers' seat, and said, "OK. Now it's your turn to back this rig straight back this road."
Reluctantly, I climbed behind the wheel and began playing with "Reverse." Patiently, time after time, he talked me through which way to turn and how far to turn the steering wheel. Over and over again I backed slowly, then pulled forward and backed up again. This went on for over an hour!
I did not run off the road (very far). I did not hit anything. I did not get into such a tight jack-knife angle that I couldn't get out. I did get a better feel for how to get the rear of the trailer to go in the direction I want it to go. I did NOT, however, master the technique of backing a 32 foot trailer with an F350 truck. I'll need lots more practice, if my nerves -- and Bruce's -- can stand it.