And again, that makes perfect sense once you are IN the loop, that someone not yet born can be your father. Since the time travel is occuring in the 'future' part of the loop, though, you still need to be able to account for an original timeline where thing progressed normall up until the point of the first time travel.
I completely get that once you're in, the original timeline doesn't matter, and it can self-create, with effect preceding cause and all that. Still have to account for the original timeline where NO time travel occured, though.
Citing an example from somewhere else doesn't really help at all, because there are just as many unrelated examples where the opposite happened so...?