A kind of proto-TAXI DRIVER?
While I wouldn't say the two films are hugely similar, DAVID HOLZMAN left with a definite impression of this. A few points of comparison:
1. Both films are set in New York, and emphasize the unglamorous side of it.
2. David is confronting the possibility of being drafted; Travis is a veteran.
3. David keeps his cinematic diary, which includes a number of monologues in which he discusses his views on life; Travis keeps a written diary, and in voice-over we learn that it contains his own views on life.
4. David has a rather shaky relationship with a young woman whom he ultimately alienates (by his invasion of her privacy with his camera), with the relationship ultimately ending over the phone; Travis attempts to forge a relationship with Betsy, but after taking her to a porno, she breaks things off with him, and he calls her, trying to patch things up--he fails.
5. David develops an obsession with a neighbor of his, watching her from a distance; Travis develops a fixation (albeit of a different nature) with Iris, although he actually develops a connection with her.
6. As the film progresses, David seems to become more isolated, desperate, and unhinged; Travis is no different.
Of course, TAXI DRIVER, which develops its themes at much greater length and with more skill, is a masterpiece, while DAVID HOLZMAN'S DIARY is merely quite good. But I think the two have more in common than one would suspect.