I've solo'd mythic dungeons on my pally. For almost all packs, its cooldown + max sotr uptime, using shining light procs for the free wog, while kiting as much as I can.
If i'm in the territory where I'm facing death and have to spam WoG to keep alive, i've fucked up long before that. Usually in sotr uptime and planning of cooldowns... But yeh, of course, if you're about to die in the next 1-2 secs, use wog...you never wanna die as tank, ultimate failure