Using alcohol to stretch leather?

Way back in the eighties, I bough a pair of Frye boots, and the salesman recommended me to spray a pair of socks with rubbing alcohol, especially the areas of the boot that were tight (damn bunions!), and wear the boots for a few hours to stretch the leather in that area. It worked, and I was able to wear those boots the next day on an eight-hour flight to California and go stomping all over San Diego for hours with nary a blister!
Well, I’ve aged into the stage where I am now wearing very expensive Dansko shoes (with orthotics), and they tell me that I can’t go up to a larger size without losing the support I get from the size I have. They fit better than any shoe I’ve ever had, but they’re still a bit tight around the bunion. They assure me that the shoes will strech as they get broken in, and I was wondering if I could speed up the process with the old rubbing alcohol trick.
Does anybody know if the alcohol damages the leather in any way? It didn’t damage the Fryes, but I don’t know if this leather is processed the same way. Any leather experts out there?