Originally Posted by
masamuneehs
This doesn't make sense. First, if the Death Note owner knows a lifespan, what good does entering "Will die on _lifespan end date_" do in the first place? That's already when they'd die from natural causes or whatever is supposed to kill them in the first place! It doesn't ensure that person will live longer, because naturally they'd make it that far anyway, but no further.
Second, writing "die peacefully in the year 3000" is impossible. So, like people who had elaborate deaths that were impossible to fulfill, that person will just die of a heart attack instead in the standard time as if no date had been set. At least, that's what Light's explanation and the rules so far have indicated to me.
Third, Death Note owners are a little different from regular people. Didn't Misa explain how she figured out who Light was? ...I need to catch up to the anime... not going to say anything else
and, sorry psyke, but i editted your post because there seems to be some stuff in it that hasn't been covered yet in the anime.