Unless you've worked a lot with 6502s or their brethren, it's going to look like a dense mass of gibberish. Not a lot of comments but excellent use of variable and label names.
Budge's assembly is some of the most clever and compact code I've ever seen for these kinds of processors.
I thought this was funny: Oddly, Budge doesn't like to play arcade and videogames very much. In fact, he says it was "sheer torture" to play pinball steadily for months while working on his construction set.http://www.atarimagazines.com/compute/issue57/computer_game....
Budge's assembly is some of the most clever and compact code I've ever seen for these kinds of processors.