Until Peter shows up with the noose, I thought Jeb was "born" recently. We were supposed to I guess. Are they saying Jeb, looking like adult Jeb with the same name, goes through all this, periodically through history, accellerated growth and trying to take over the world, only for something to go wrong? Maybe... what we saw was only the second time? I suppose he got gaoled for his similar Leviathan activities, so not his fault, and they let him try again? Why then does the world seem so new to him in 1969?
Same as with Eve I suppose, rebirth is a hard process and much gets lost. Sort of what happened with Julia when she hit 1840. Crossing these barriers take bits of you away.
This must have been Jeb's second try, only. If he betrayed them this time, he has an inclination for it, and wouldn't be given repeated shots at The Plan.
It disturbs me that even with Jeb, they seem to have been trying to make him genuinely "reformed" and virtuous, just because he suddenly turns over a new leaf. It makes me wonder after seeing Barnabas's not-so-gradual or understandable process of reformation, in 1968. I wonder if the writers were harboring any murderers in their basements, or something, or had "pasts". Before, I always thought it was cool that they questioned the rightness of having the law "redeem" people, but over the years there are just too many examples on DS of reprehensible people waking up one day whistling and redeemed.
Arashi... I think they must have had that in mind, what you said. It was just poorly explained. By them, not you.