What 4 other heals do sorcs have that can be spammed?
1) revivication requires a 3x proc from innervate and has a 15 second cd
2) resurgence has a cool down 6 seconds
3) Shield can be spammed but not on same player due to ionization
4) Cleanse has a cd 4.5 seconds
Rotate between those heals and innervate and you can always be casting something really hard to interrupt. You don't need all 3 procs to cast Revivification. There's a pretty good chance the 2 stack or 1 stack version will slip through and if it gets interrupted you can always cast a big heal instead. The procs for revivification is there to preven the worst case scenario where you spend 1.9s casting Revivification and have it interrupted and that gives the enemy enough time to try to burst you down. With even 1 stack it's way harder to attempt to interrupt it at the last 0.1s so either it gets interrupted much earlier or not at all and either outcome is fine.