Correct me if I'm wrong, but I was always under the assumption that the terminology of the "Varial Heel's & Varial Kickflip's" came from vert skaters, as they would essentially be doing a varial by grabbing the board. The whole "Kickflup Shuv & Heelflip Shuv" term came about in the early years when vert started to die out and everything went to street, since there was no grab involved with doing the trick on flatground, the concept of calling it a varial seemed irrelevant and unnecessary.