Finally got to try my '88 11hp in the rough (sort of). It did well considering I have no experience with any other riding mower. Seemed to spend a lot of time on 3 wheels, i.e. 2 rears and a front. I also had trouble shifting a few times when on a slope because using the brake to hold it still also keeps it from moving a smidge when it changes gears. At least that's what I think happens.
I towed a wagon, similar to a radio flyer type but modern wheels and folding canvas construction. I used a tie-down strap hook on the tractor end and attached the strap to the wagon by its handle. When it was loose it chose it's own path and this didn't work well going down hill. A stiff connection is a must for down hill, lesson learned.
Weeks ago I started building a path where the slope reaches 15° but a dead tree has fallen half way to it so I couldn't just head for it. My crew was bored and started doing work-ish things so I had to help them or feel bad about frolicking on the machine while they worked. Part of what we do is finding nice building block rocks and bringing them down to make stuff, like a curb or a fire pit. The crew decided that they would rather carry rocks or pull the wagon down hill by hand. Pulling the wagon up hill empty is easy so I parked it for a while.
I was waiting for a break in the rock handling so I could use a chainsaw to deal with the fallen tree when it started raining. I wanted to see the property in the rain so it was good for the plan, but the tractor was done for the trip.