Yes, because that makes everything SO much better. "Hey, don't worry about all the killing we're going to do THIS crossover! The next one coming is going to undo everything anyway!"
I appreciate the thought, but I try to go by two basic rules for comic death. 1), it should be AWESOME, in-character, and rare. Barry Allen's dying was that way. 2), it should goddamn well STICK. If you kill someone, it should be thoroughly thought out, planned ahead, and not retconned! (Barry Allen's death WAS that way.) MOSTLY dead, NEARLY dead, hanging on by a thread, all these things are okay. But if you kill someone, let them rest! It just makes the whole thing so meaningless when you keep invoking a revolving-door afterlife.