Have to have a total grip on the whole scene all the way up and down. It's a long "walk". The first time I went over in a big unit, I raced a cyclist the whole way, they left me far behind on the way down. And there's a big hook curve near the bottom, by Wilson, on the Wyoming side.
I went over that pass, a long time ago, with my mom and nephew in an RV. It was late in the day and a few miles from the top, a moose jumps out onto the road with her calf and trotted along side us for a moment, looked in the window at my mom and she freaked. My nephew was pretty young and wasn't thrilled either but I also could not stop on the way up on a 10% grade. I was only going about 18mph. Fortunately the moose mom had mercy on us and took a quick exit over the guardrail, where she seemed to be headed and we made to the other side in one piece.
Fun times on that road. 
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