think parry would literally need to have a counterattack mechanic to it to become even remotely desired lol for example it mitigate the base 20% + auto-attack damage instantly to enemy (with tweaks etc otherwise its too op) Might even need to have different affects by tank class. Quite frankly axing it might just be the better solution with it being a flat 20%

edit: for a while in 2.0 i thought it countered :P