Considering it costs gems to move realms, and you only get half the rewards from the arena...it becomes useless to transfer realms to farm gems in arena. Making it to where you can only move once, period, takes away the ability to switch guilds, or to liven things up and make guild warfare interesting when one guild dominates in the realm. (At least on my server, anything over server 11 has server warfare....us folks in 1-10 still have realm warfare)