As I noted, it's nicely numerical, even if it isn't terribly scientific! The arbitrariness of divisions that matter is where the hand-waving and faith come in. On the other hand, the fact that you can choose whatever categories you like, and fit them to activities that truly matter to the campaign, makes it flexible (even Fudge-like). I happen to like the log-of-points approach, too, because it flattens things out into a small range which is easily converted to "dots" or "levels" in other games. Tinkering with the number of skill sets and the log base could let you match just about anything to anything else . . . although as we've both identified, one does need to have a few hours for it.