Madness reigns at Grognardia; sanity prevails at Wondrous Imaginings.
I respect James Malisewski a lot, but posts like this leave me scratching my head. You don't get anywhere trying to explain objectively why Monopoly, cricket, chess, barbeques or grapefruits are good. People like them or don't like them based on entirely subjective reasons. Why should a particular style of role playing game be any different?
The idea of a "clear and rational" argument in favour of a game is about on a par with somebody sitting me down and trying to explain why Metallica are good through reference to their sheet music and an analysis of chord changes; or maybe a girl I'm not attracted to trying to explain "clearly and rationally" why sex with her would be a good idea. Ain't going to happen.
EDIT: Or, for example, somebody trying to explain why Star Trek XI is better than Star Trek II by appeal to logic.