If it's dry you can ride the wall, pedal hard into it and let momentum carry you up onto the wall, put your weight on the downhill pedal to help your tires stick, and arc back down for the 2nd half of the downhill. It's fun. If it's wet you can't pull that off, you have to gingerly ride the rut...and if you have to walk it, or if you fall, that's not defeat! Hope that helps.
Caveat: there have occasionally been bones broken on that descent- so it's better to walk it than it is to hurt yourself- but it's really fun to have some technically challenging trail to ride. Most trails in Michigan require pedaling to get your heart rate up, Robinettes can get your heart rate up in a couple of places with just anticipation!
"For every man who is chopping at the roots there are a thousand who are swinging at the leaves"
-Henry David Thoreau