Answer: I rubbed through the back of a pair of my old J&M's (from back when the top of their line was a decent shoe). They weren't uncomfortable, but I decided to make them into rain beaters and as part of that had my cobbler replace the lining with something that is sturdier, softer and slightly thicker (in hopes of reducing/eliminating the heel slip). They're still in-process, but they showed the heel lining to me the other day - looks good and I think it will work.
This Q&A was first posted in our Official Shoe Care Thread.
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