Hi,
Thanks for the interesting discussion that shines a light on tire size.
I'm currently using Conti Touring tires with a flat bead and a grooved (side?) Size 700x32. My rims are WTB 22?, Tiagra hubs, that came stock when I bought the bike in 2007.
I'm interested in exploring the idea, or buying a new set of wheels, so I can ride my Volpe (cycle cross) bike on dirt roads that can be slippery when wet. I'm interested in exploring some tea field farmer roads. My idea is to have a second set of wheels I can simply swap out for riding off road in a size like 700x38.
If it matters: My brakes are Cane Creek cantilever. My STI shifters are Tiagra triple with front crank sizes 28,38,48.
What are your thoughts on this? Is it better to buy a mountain bike for this purpose? (I doubt I will do any single track here.)