Incidentally, it seems to follow from this line of reasoning that quite a lot of the brain is unnecessary, also. Though the state of the art in neuroscience is nowhere near up to being able to freeze just the necessary bits.

It leads to an interesting thought experiment, though... if I can only preserve enough information to allow an N%-match copy of me to be constructed at the other end, at what point does my intuition that "I" have been "brought back to life" (or teleported, depending on the particular intuition pump being used) collapse? What tests would I want to have the terminal point use before certifying that the constructed person was Dave, and what would I want them to do with people who failed the test?

My own intuition is that this is really no different than the question of whether I'm the same person I was 20 years ago, all we're doing is playing with how strongly privileged the default answer is. The more exotic the process, the less confident we are in preservation of identity... that's all.

If that's true, then if reconstituting people from frozen brains becomes commonplace, we will quickly develop just as much confidence that we really are the people we were as modern-day septagenarians have about their adolescent selves.