Is is

Is is is (the double copula, including was was, the thing being is etc) now more or less standard, or at least unremarked? John Humphrys on the Today programme on BBCR4 had a bit of a campaign against it a few years ago but now most people around him seem to use it unnoticed - and no, it is not just a hesitation-type reduplication as several linguist say, perhaps because they do not want to be thought prescriptive. Did it begin as an imitation of influential Americans like George W. Bush (but not, I guess, his father)and John McEnroe, two early users?