User blog comment:AP Sejuani/LYCaN, the Advanced Prototype (COMPLETE RELAUNCH)/@comment-7709681-20141124215716/@comment-26055105-20141125010934

Perforate's Armor shred stacks, yes. I forgot to mention that. The thing is, each stack only lasts 3 seconds, which happens to be the cooldown of the ability at max rank if you don't have CDR. You can get 40% armor shred for a brief period, but that relies on you landing both Qs, and you won't be able to get the 40% shred for another 10 seconds because of the ramping cooldown.

I was referencing Runaan's Hurricane more than anything when I made the point about Oblivion Blades.