I have been using Mr. Tuffy's since January. i do not have any signs of my tires(Gatorskins) bruising. However, If someone bought a size too big I think it could happen. Some of the online Internet shops and maybe the LBS may recommend the wrong size. I know when I bought mine off the AEBike website the sizing was not clear. I had to refer to the Mr. Tuffy site to decode the sizing colors. So, buy the
right size.
So, maybe someone ordered the wrong size from the LBS before and it bruised their tire?
Also, it is important to "set" the tubing, Mr. Tuffy's and tire correctly when installing. Not a big deal really. Just means to take your time. Partially inflate the tube. Sliding your hands around the wheel before fully inflating pushing everything in it's right place.
Btw, one of the guys at my LBS advised me not to get the Surly Cross Check due to the frames breaking at the seatstay. I have a Surly Crosscheck. I can assure you that the 4031 steel frame is stronger than anything in that LBS.