It’s been decades, literally, since Johnny Carson made jokes about the Flying Wallendas – but here’s one of them, daredevil Nik Wallenda, doing a live stunt in which he walks a tightrope across Niagara Falls. It’s a stunt that was banned more than 120 years ago, but here he goes… albeit on a wire so thick he likens it to a sidewalk, and with a harness that will prevent him from falling. Unless he removes it, which some advocates of live TV are rooting to happen. My