To maximize self-heals and blood shield, you need to time your death strikes for AFTER you get hit HARD, which means you are now 1 shot away from death. This is a "death strike moment." You also need a solid mastery number, which you won't have if you've regemmed/reforged 1562 points to cap both hit and exp, unless you've already farmed all the best 378+ gear available.
If you don't land the death strike in that moment, you will die, and it's not your fault. It's all RNG RNG RNG at that point.
Precisely the point where the possible changes to "make it better" need to be thought with care, and maybe... Just MAYBE, for once, blizzard could come up with a system that can actually make DKs more resillient or get the mechanics of the class to be able to scale properly with the difficult at hand, without having to nerf it all down to the point where it shouldn't exist anymore due to PVP aspects of the game.
Sure it seems hard as hell to make an hability work in X way against players and in P way agains mobs and bosses and everything else that isn't PVP, but isn't that the point of PVP having specific gear and specific talents and specific stats?
It's something supposed to work differently and as long as every change is made through the road of "not getting near anything that could change pvp", our options (well, their options) are limited as to what can be done...
Earlier up there I've posted some crazy ideas a couple of friends started babling on gchat and you know what? As long as Blizz could separate the way things are triggered and the way specific habilities work against or in response to players OR pvE enemies, even ideas such as those could be viable after some (a lot of) tweaking...
After all, it would be kinda dumb to expect a mechanic that buffs up heal recieved and total health from a player once he gets into combat, or gets hit, or uses some self-heal tool to apply to PvP combat, since that would make it absurd to go up against such a class... But PvE-wise, a passive/active mechanic with those effects could help a great freaking LOT when the class is supposed to tank and has "no" passive mitigation to make up for the very larger ammount of damage he takes.