I have been sitting around reading old threads about touring frames. Two points seem to come out.
1.) 26 inch MTBs make decent touring bikes.
2.) Touring frames with long chain stays handle better because the pannier can be moved forward over the axel without causing heal strike.
However, I never see anyone complain about their fully loaded MTB touring bike not handling well. Because most touring frames are designed for 700 cc (622 mm) wheels, I am wondering if the 26 inch (559 mm) wheels on a MTB help mitigate the handling issue. According to my calculation the 26 inch axels are 3.15 cm closer to the ground assuming similar width tires i.e. 1.25 inch vs. 32mm. This is seems like a big difference even if the BB is higher on the MTB. It seems to me there might be other reason why a 26 inch tires may help stability that I am missing.
Also, I measured my Marin Palisades Trail this morning and there is about 2 3/8 inch space between my size 9 sandle and my Orleib pannier on my Jandd Expediton rack.
PS I love the Thorns but they cost too much.