Interesting, and I'd recommend it.
I first rode that ride with a 53/39 and 11-26 rear. I figured it would be fine, and though I wasn't in top shape, figured I was OK.

The night before, at our dinner, a group of young, fit riders came to eat, all modern bike riders, but good chaps nonetheless.
One of them asked me what I was riding, and I told him "regular double, 11-26," to which he replied, "You are going to have some trouble."
He was so polite, and didn't laugh a bit. Like Chrome Molly, he had the ability to think of the obvious without crushing the uninformed.

Thunder Ridge enlightened me to long-cage RD's, where I ran a 53/39 and and a 12-32 9-sp (DA, rare RD, I know).
The 39/30 was good for all but the short, rude hillets at Peaks of Otter, where I went to the 32. It was my "bailout" gear.

Since then, I've looked at gear-inches only briefly, as they're confusing. I'll be running 50/34 -->12-29, medium cage RD, in SW Wisconsin.
I have a 53/39 -->13-34 bike available, 56cm, if someone wants to give it a shot, 10-sp DA DT shifting, fairly fool-proof.
I've often wondered what the Dare would be like with a 650c bike like a Paramount 7-series 650, and a compact setup.

Thunder Ridge has more rolling stuff before the long climb, and then some meandering between the little sharp climbs.
The Dare has a lot more of either climbing or coasting, less mileage of ridgelines or river bottoms.

iab's Bartali ride had by far the best mix of hills, descents, and scenic countryside, spaced for recovery.

By the way, if you haven't sent me your name, homebase, and year/make/model of bike, please do, so we can get you on the list.