The vast majority of alliances these days are over rated, it has become common practice these days to try and represent your alliance in as godly form as can be to the public. This game of deceit is an art form to some alliances, and any deviation or honesty shown as to the real potential any said alliance has is quickly frowned upon. Truth be told, the inflation of stats in the game has certainly gotten to many egos and often, even to allies, alliance leaders will grossly overestimate everything from their political stability to military poweress. This is all done, of course, for the pursuit of actualy having the right to claim the very statements they state now.
I only hope that at some point these paper tigers will fall apart to make way for the rare alliances that aren't bluffing.