I'm running an old triple and 8 speed road cluster for a low of 26/23. It's fine.
I've done the fully paved climb and descent on Bohlman many times on my road bike
with a 39/25 or 39/27 depending on what wheels I run.
I've seen my cadence drop to the 30s up a couple of 20+% sections with those gears
if forced to the inside of a couple of the turns by cars passing me on the uphill...