Ok, one last stab. You are going to be copied and teleported to 1000 different planets. Only your body and your brain will be copied. On 999 of these planets, everyone speaks Spanish, and on one planet, everyone speaks French. You don't know either language, and you are only allowed to learn one of them before your departure. From my perspective, learning Spanish is the correct choice. From your perspective, there's no reason to chose one over the other. Is there?
I would learn Spanish before teleportation, in order to give my descendants the best chance of success; but going on what I said above, I shouldn't care at all, because I'll be dead and someone else (or 1000 others) will take my place!
But you will be dead in the same sense that you will be dead in the next instant, at least with what I understand when you quote Parfit. In THAT case you shouldn't care at all in the presence of any possible threats, no?
(BTW, concerning Parfit, he still believe (in his book "Reasons and Persons") that we are "token". I have already argued that with the comp hyp we can only be "type". That means we cannot been made singular. The only argument Parfit gives for our token self-identity is that we would be immortal if we were type. That's not so easy, but even if it were I don't think it is a convincing argument.)
I don't think we need a sophisticate theory of personal identity for understanding the consequence of comp. We need just not to confuse the first person, which are not duplicable, from their "body" (third person describable) which are duplicable. Your comments and answers to Kory seems rather unclear to me. What do you mean by "I'll be dead" giving that the comp hyp makes you dead in that sense (annihilated and then reconstituted) at each conceivable instant?
Actually you do the 1/3 distinction when you say "someone else (or 1000 others) will take my place". it is "someone else" from the 1-view, and "1000 others" from the 3 view. Now we must derive physics from the 1-view of 3-splitted-differentiating machines in platonia. OK?