Is that where they came up with that just-pulled-it-out-of-their-ass idea that if you go back in time and touch your past self, you'll morph into each other and die a horrible death? Funny, I seem to recall an episode of DS9 where that happened to O'Brien, and he was just fine.
It was a misunderstanding of the pauli exclusion principle, ignoring the fact that a person even one second forward in time occupied different quantum coordinates anyway so nothing would happen. And cells replacing themselves in a few years.
They went with two humans having the same particles for life, so when two "identical" sets met, they underwent the exclusion explosion.
Poor physics, crappy scene.