I think part of the problem is the junk that gets through U/L testing. It looks like if it doesn't simply burst into flames on the loading dock it is OK.
They certainly don't look at longevity when they approve things. A while ago I had a Carlon rep tell me RNC conduit body covers and RNC straps were not required to be UV resistant ... and they weren't. Here in Florida they won't last more than about a year.
