Probably not the real story (see above), but my initial interpretation: The two characters are named "Al" and "Lance". Say "alandlance" real fast and it sounds like "Avalanche".
Well that's what he says. I know if I have an idea I'm unsure of, what I'll often do is say it came to me in my dream. That allows me to step back a little from that idea ...even though dreams are strongly affected by waking life. Sometimes it's literally true, and sometimes it's a convenient fiction, and usually for me the truth is somewhere in between those two poles:-)
Haha, well ... I'd be inclined to believe what an actor in a film, or the director of the same film, tells me about how the title of the film was born / came to be you know?
R.I.P. to a great AND beloved American film Critic, Roger Ebert.