Unless Moab is vastly different than CO, I agree with the others, you're more likely to see long, sustained grades in the 6-7% range rather than big double digit climbs.

I ride a double in CO, and yes, I sometimes cry up the occasional steep thing. I'm not in that great of shape, and honestly, It doesn't take me that much longer to start crying on the mtb with a granny. (and I could change the cassette on the roadie and help myself out a lot).

The big thing is the altitude and there's not much you can do about that unless you are willing to show up a week early. I can't believe how miserable I feel after spending 2 weeks at home in GA then showing up back in CO and trying to ride.

Anyway, I vote bring "Pinkie" and maybe consider a different rear cassette or smaller front ring if you are still worried (talk to your LBS about your different options).