I've seen MJD a few times and love it.
What's your question?
The ending is great, imo. I love Walter Brennan and "hEE-Lots".
Ever since the first time I saw it, I have felt the ending is a bit forced and somewhat a cop out. He gets up to the roof, and just when I feel he should do the daring thing and jump, his pals show up and give a corny speech, and he walks away. I know Capra et al had trouble with the ending, but this just sort of feels like they wanted a way to keep John Doe from dying and the grabbed the first idea they could think of.
Why do you think it works?
The obvious answer, of course, is that it IS Capra and no one wants to see Gary Cooper die at the end of a movie but I think also, it is about having hope and trying to trust people.
Every time I see that movie, I want to go door to door in my neighborhood and introduce myself. I generally know all the people in the houses around me but I would want to go even further. I've never done it but after seeing the movie, I am usually more open to waving at folk as they drive by. (Maybe I should rent it soon or watch it more often! lol)
The movie is corny, in some ways, but there is some real truth to it. The Brennan character is exactly the way I see one of my friends. He has a disdain for all things "normal". He's a real anarchist.