changing one avatar by 5kb or 20 px wouldnt make a difference to 56k users but if every avatar/signature that has to load is bigger, that value does add up, and if its a particularly slow day on the internet they could be there for hours.
personaly i couldnt give a shit, as im on 2.2mb bb, and my avatar is designed to be 80x80
(so dont put auto resise [up] on if you up the limit, i dont want it at 100x100)
Hope in reality is the worst of all evils because it prolongs the torments of man.
-- Friedrich Nietzsche