User blog comment:YourPrivateNightmare/Hail the hourglass!/@comment-5545048-20130913202404/@comment-5907289-20130914210502

I agree in certain very rare situations it can work, Zed being a prime example; but if an assassin has a single CC that prevents you from activating Zhonyas, a GA would work better.

Also, Vi knockup is like 1-1.5 seconds? While Zhonyas stuns you for 2.5.