I agree to a point but I doubt that Orcish was so precious that Shagrat couldn't have had a different name. My sister, who sneered at Tolkien for years until she became possibly the world oldest Leggybopper nearly crashed her car when she caught that part of the BBC adaptation on the radio ..... even with the careful stress employed by the owners of Shih Tzu dogs...
When one of the disparaging reviewers of CoH said that Thingol was the silliest name among Tolkien's characters I knew he probably didn't have a good knowledge of the oeuvre...