Yeah, it's possible, but essentially useless. The point of getting to T12 , is to maximize the potential use of all of your abilities. Using Felwinter, you lose your super, so any filled tiers on your intellect, and anything over max on the others is all wasted anyway. You get the extra grenade and melee, which is almost like your cooldown being 2x as fast, but if it's not benefiting you more than your super would, that too iss a waste. I use Shinobu's Vow,.I get the extra grenade, and I get to use my super, which I find way more beneficial than an extra Blink-Strike. Having an extra blink strike wouldn't be very beneficial to me, especially if I'm T11 or T12, with the Fast-Twitch perk selected, my melee cools down really fast anyway, and is almost always ready whenever I need it.

It's cool man. I see that question come up pretty frequently so it's not just you :p