PLENTY of us use run-walk intervals. Really, if it's good enough for an Olympian, why wouldn't it be good enough for we mere mortals? I know plenty of people don't use walk intervals and that's fine, too; different strokes for different folks, we're all an experiment of one, 26.2 miles is 26.2 miles, and so on. I'll be happily doing the :30/:30 intervals that allow me to run long distances at all as an aging ex-athlete, TYVM.
Honestly, some of the elitist comments here lately are getting to be a real drag. And you know it's getting bad when I say something - folks who've known me here for years and years know I'm usually Suzy Sunshine, trying always to give every post's intent and tone the benefit of the doubt.