That makes perfect sense to me. If you pop yourself over to another reality, you pop that version of you OUT. If HE comes HERE, he pops YOU out.
Uhh, to where? What happens to the version who's "popped out?" Do they get shoved over into the next quantum reality? Do you get a whole domino effect of duplicates getting pushed one reality over?
Or do you just switch places with the other guy? I think that's what "Parallels" implied.