If you watched Mugen Train, and didn't cry at this song, then you obviously watched the wrong movie. Still can't listen to this whole song without tearing up, especially 2?59.
I think the ability of a single song to make just this amount of people emotional and myself for like the 281037482029th time should say something about the talent of a singer and the skill of a story writer working together. With a character that came and went within like 1.50 hrs of a movie no less to make them so memorable. I applaud that kind of talent