Ashe + Oppression Mastery

Oppression is a 1-point Defense mastery that decreases all damage taken by units affected by most forms of CC by 3%.

So (virtually) everyone that gets hit by Ashe' W or autoattack deals 3% less damage to her just because her summoner put 1 point into that mastery. Awesome.

I mean, she doesn't "do damage" anyway, quoting salty yoloqueue players, but heck, maybe they're right for once. She doesn't have steroids, her passive is goofy and the only low-CD damage she has outside of her autoattacks is her W which drains mana and can be bodyblocked. So she might as well be able to live awhile longer, right? Make use of some of that CC? Maybe.

And if anyone's not going to run 21/9/0 masteries on a carry than they might as well leave offense masteries at 9 and put the rest into defense and utility. A 9/10/11 spread might be good here; it used to work for Ryze (awful comparison I know lol). The 3% LS/SV is a decent perk, as are the bonus MS and mana regen. They're not OP or anything but it's still all stuff that carries like.

Does anyone think Tanky Ashe with the Oppression mastery might be good? Or will Ashe always be Trashe?