Really a terrific thread, this is one of our (my wife and I) favorite activities.I haven't had a chance to read it all (new here).
I have to peruse the posts, but I'm looking for any sort of info on how long and to what degree balls turning blue is a damaging activity. I see lots of pics with pretty blue balls and as I'm trying to stretch mine sometimes they can get slightly blue for a fair amount of time.

CutUp