I didn't read all the replies but I belive there is aperfectly scientific explanation . . . . that will still leave you with a question:
I think Time Bastard is only referring to the occurence at the exact point in time. So even if the the doomed time traveller travels back in time, he doesn't escape the flow of time. The reason I say you would still be left with a question, is because this somewhat validates the Time Bastard theory, in that, even if the created branch duplicate of the individual isn't outright destroyed by the original time traveller's return, the doomed duplicate must always travel back in time away from that exact point in time, being, in a way, then destroyed. Theoretically they can't even travel foward "past" (ha ha, see what I did there, but no pun ._.) the exact point in time because the theory states they must be destroyed.
Oh, I almost forgot: the branch duplicate (or original pristine non-time traveler) would need a reason to travel away from this point in time. There's is nothing in the theory to suggest the branch duplicate would have any means of attaining this information (especially without ever time traveling in the first place) hence, even though I shouldn't laugh, it being called the Time BASTARD theory ha ha ha ha. Hapless dupe.