Only did one tour, but it was pretty long (2,000 miles) and reasonably quick (55-96 miles per day, avg. 65miles/day). Loaded tour ~40-50 pound of gear and water on bike.

700c wheels, 22 tooth chainring, 34 tooth cog ~ 17 gear inches. Satisfactory for most hills, but I'm working on gearing down to 15 or 16 gear inches.

Riding slow on tour up hills does not bother me a bit, in fact I found those times at around 5mph to be the most relaxing, where I could see my surroundings the best.

OTOH when I hit NY State I encountered repeated hills where I had to strain and push hard, even at 17 gear inches. NOT fun.

Nothing wrong IMHO to gearing ones bike down to the limits of rideability (3mph??), there'll still lots of ratios left to accommodate faster speeds.

Mike