Been there, done that one. I grew up on narrow and wide front ends and we farmed steep hills - C, D and E slopes predominately. Heading down a steep hill with a Farmall Super M and a load of bales. Tractor popped out of gear and I thought I was a goner. Guardian angel was working overtime that day.
I also agree that you can roll anything, given the right circumstances. However, I will argue that the margin of safety is somewhat less on a narrow front end assuming all other factors are equal (tractor height, weights, tire spacing, etc). Those factors can make a huge difference in stability, and with the right setup you would likely see the wf flip first (an extreme example would be a wf high crop vs. nf Case SC). When we went from 38 to 30 inch rows, it was amazing how much tippier our tractors felt because we had to narrow up the tires. And that was on large/modern tractors.
One nice thing about running a wide front is that the front wheels hit the potholes and stumps first so you can stop before you hit them with the rears. With the narrow front, the first you know about them is when you feel the rear hit them. At that point, you are committed and what's going to happen is going to happen.
We live in an area with a lot of people moving out to the county and buying tractors. Not many of them realize how quickly things like this happen. We just had a elementary school age kid killed when he was riding with his father bush hogging and fell off the back. The mower ran right over him. As a father, I can't even begin to imagine the anguish that father must be in right now. As a casual observer, I have no idea why he allowed that kid to be there in the first place.
