... if you leave a moist carpet against it all winter. It happened to a friend's boat who wrapped an Awlgripped mast. I use a canvas cover and haven't had an issue, probably because it doesn't hold water and dries out.

BTW I've used carpet with no ill effects, but the hull was gelcoat finished. Now that it's been painted I might change to ribbed rubber pads. Seems safer, however with rubber or vinyl I think might be more critical to make sure the pad is clean.