It doesnt have a good beat and I cant dance to it. I give it about a 3, Dick.
Not a particularly good theory of the many out there and doesnt stand up to much more than cursory examination. Youre never going to create runnels of that length to depth ratio by slowly removing a much softer material from around something much harder. Ignores a lot of other things. I would imagine that someone could write a whole book about just this subject if they were that motivated. Id rate it slightly better than alien woo woo but not quite up the the handwaving of most gate guardians.
So sandstone is hard? Who know?