Really?
Another..."Something doesn't work the way I want it to so it must be broken ".
This is actually a case of it not working the way
they wanted it to, because the death check occurs at the wrong point in damage calculation.
What's supposed to happen: raw damage is run past mitigation to get adjusted damage, which is then checked against player's remaining HP when 'rolling' for a kill-cam hit
What
actually happens: raw damage is checked against the player's HP when 'rolling' for a kill-cam hit
This is especially noticeable on higher difficulties and at higher levels, when the player often has extreme armor ratings and HP in order to survive due to amplified enemy damage. For example: a L40+ Draugr Death Overlord (one of the main culprits) on Master can deal upwards of 800 HP in raw damage per critical strike if wielding a 2H weapon. Now, a player with capped armor (80% physical resistance) will reduce this to 160 HP per such strike, which is eminently survivable for a character of those levels given the usual HP amounts thereof; however, the 'instant-death' check is made before taking mitigation into account, so said character is eating all 800 points instead, which is guaranteed death to all characters save those who engage in extreme HP stacking.
Note that this does not mean that the kill-cam hits themselves are a bad thing, since they really aren't; rather, it means that their flawed implementation has turned them into a bad thing, especially since they lock out the controls for the duration. If either the lockout or the order of operations were corrected the majority of the complaints would disappear, since then there would at least be a chance to react in some manner.