Got to ask why though?

It is niche enough on Plds that it wouldn't hurt but nor would it really be beneficial to other tanks so what's the point if it was old Cover might be more worthwhile but as it is your asking the skill to be uncoupled from pld gauge to be a free cd to all tanks including pld, which means they will probably nerf it again.

If you want to look at why I think this look at Repose on healers, Sch and Ast never needed sleep, they had more than enough tools to handle things without it, yet Repose was taken from Whm to be given to Role Actions for a single quest that is lv80, and has since been removed from my hotbars as they never needed it before or after, SE doesn't even design stuff with healers having sleep, 1 quest does not justify a skill to be taken from 1 job to be given to the role.

Unless SE were to design things around all tanks have cover I see no point taking it from Pld.