A question for the DM's out there, how do you go about handling PC deaths & why?
1.Luck of the dice, if you get killed that's life.
2.Wait for grand finale, so they can go out a bit more heroically.
3.Hardly ever and then only ever to progress the story or serious climatic moments.
I think the real first step is to explain how deadly the game is to the players first. Maybe they would rather you increase the Massive Damage threshold so they can keep thier characters longer. That's not a huge consolation on your part as GM. Perhaps giving them a fourth fate point that can only be use in case of death. That maintains the threat of demise, but puts a great deal of power in the players' hands. 3 fate points is really enough to get them through most basic adventures and even some of the more challenging scenarios, IMO.
On the one hand, they have to realize that they can die. Doing dumb things or taking unncecssary risks can get you killed - that's the facts. That said, if they fail to make a spot check for a deadly trap that could get them killed - you know, a one-hit wonder of a trap or something - then I'll give them several ways to get out of it.
As a player, I always hated dying because I simply fell in a pit or some other instantly deadly thing that my party and I simply didn't try and roll to find because we're preoccupied with other factors, usually story based. I'd say that if the PC is going to be in deadly jeopardy from instant death, but he's put himself in harms way out of interest in the story...let it go, or give him that extra benefit of the doubt.
Going down in combat or being careless or frivilous is another matter.
I had a player in a COC game that got very frustrated with a doctor at a sleep clinic and decided to break in to the clinic under the dark of night. Somehow he failed to take into account that he could just enroll in the program or schedule and appointment with the doctor, both options that were laid before him quite obviously. Eh...so he wanted to play the tough guy investigative reporter...I'll let it slide. Now, he knows that during the day there are at least two goons with guns, so those guys might be trouble. He also has low skill in picking locks, but is surprise when the records room and chief of staff's office is locked. He's broken a window to get in, silently enough, but forgetting that people will notice the broken glass in the morning - glass in a window leading to the room where the patient records were stored, which he'd been asking about the previous day. He was so surprised that cops showed up to arrest him for B&E.
Now there's no death there, but I could have had him shot by a clinic goon. I avoided it because I wanted to teach himn a lesson (how poor role playing choices can backfire) without doing him harm. He got it.