>>95192662My theory is that as the end approached Genndy got cold feet about not sending Jack back to the past and he decided to do so despite the theme he had been writing the whole season. Whatever he had chosen I would have been fine with; both options are viable to me, although I have to admit that I would have preferred it if Jack stayed in the past.
It would still leave him unable to die, though. Ashi might be immortal too, but still, being alive until the sun blows up is a little messed up.