Okay, point taken. Makes sense but still, this system has its disadvantages.Most, if not all, systems do.
Decay will promote an active ladder and the players who can climb will feel rewarded by no longer being #2 after a player who hasn't played since beta.
You call it undeserved, but what merit is there in someone who hasn't played in 2-3 month being #1? Far more warranted if he would be here to defend his position, would you not say?