I've heard of professional ski tourers doing the JMT a number of times. I was able to do the stretch, with a big variation, from Yosemite Valley to Mammoth. Although I went on snowshoes: I forget how Orland did it. There are groups who ski a portion of the route; no one much has the time for a end-to-end solo, it seems.
There was a magazine article about the feat, although I can't remember when or where. More Sierra history.