Honestly, it's not a problem. If it were anyone other than Kitru complaining, I'd be pulling out a "L2P" right now. Maybe I just have good healers, but they certainly aren't complaining.
Normally, I would be pulling out an L2P as well, and I actually *did* when we were testing this stuff on the PTS, but it's become apparent to me the more I play my Shadow tank that it *is* a problem. If a Guardian or VG in my level of gear runs into an FP, there isn't a single time where they actually *need* to burn a CD in order to survive (Guardians will often burn Saber Reflect but that's more for the threat generation than for the actual mitigation). There is at least 1 pull in *every* Hm FP (and often 2-3+) where, if I don't start off or use Deflection or Battle Readiness almost immediately after the fight starts, I stand a *very* good chance of dying. I dramatically overgear the content and yet, because of the spikiness, I can still die. That's a problem.
I shouldn't *have* to burn a CD to survive a trash pack when I'm tanking a piece of content I overgear while running with a healer that's appropriately geared, and, yet, I am. It's either burn the CD or stand a *damned* good chance of dying (seriously, in my experience, it's something like a 50+% chance on some of those dog packs) because I'm gonna get my face beat in by the world's most vicious alpha strike. I've learned enough about tanking the HM FPs as a Shadow that I use my CDs and don't experience any problems, but tank CDs aren't supposed to be for getting you through trash; they're for getting you through high damage boss phases or times when the healer dies or something similar. Being forced to use them for trash packs in standard scenarios is completely counter to their actual intent.
In ops, it's generally not as big of a problem because you don't have major alpha strikes and, if the Shadow dies due to a massive spike (this has happened to me more often that I care to admit), there is a second tank to cover while they get a brez. It's still a problem however. The best example is, and I'm going to bring this up a lot in any discussion of spikiness, Operations Chief Terminate: it'll hit a VG/Guard for 22k and a Shadow for 32.5k. Vacillation between incoming damage on that scale for big attacks like that is just *not* something that should happen.