Thanks for all the responses. Unless I missed something it seems we have lots of opinions, but not much in the way of facts. Opinions seem to vary widely. Some view the load rating as the "bleeding edge". On the other hand, one poster believes a tire can carry 5 times the load rating providing it does not overheat. Most of us seem to believe, as I do, that the loading rating is indeed a safe load under typical driving conditions including highway speed and hot weather.
I think I will try some additional internet research.