Whenever this wheel size debate is raised I think that it is a miracle that I have survived self contained international and Divide Ride rough stuff touring using Schwalbe Marathon XR 700x47mm tires. Baja washboard, Andean dirt and pumice, Canadian roots and rocks, Divide Ride gravel fire roads and local shale and granite trials have not managed to destroy them.

I have found that using high quality equipment [particularly tires] combined with a conservative riding style off road and low equipment loads prevents most touring equipment problems.