He stayed on the train right...right?

...I actually read this when it was first posted, but I forgot to review then...however, I'm actually kind of glad I did, since, rereading it now, I think I finally understand it. It's metaphorical for Zim leaving the planet—"going on a track beyond what Dib has seen"—and Dib's afraid to go with him, to leave Earth, right? Well, whatever the deeper meanings, it reads extremely well, as always, and the ambiguous ending is a perfect fit.

This is very interesting; though extremely vague.

I like how it leaves the reader to create their own perception.

All in all, I love it; wonderfully written.

Um... I'm sorry to say, I don't understand what this is about.