Every other mastery amulet that drops in Wiz can be traded through the shared bank except those dropped from Omen Striborg. Given KI is try to encourage dual school play through top level dual school gear sets (merciless), we need mastery amulets to achieve this and restricting the trade of any rare drop like mastery amulets, defeats the purpose intended. Additionally since we don't have any trained blade for another school these mastery amulets are even more useful because they give a school blade too.
