There are many things this film does really well.
First of all, the acting is superb throughout. Grodin is brilliant as ever in a very demanding, heavy acting responsibility - had he been average at it, the film easily loses heaps of its ability. Jeannie Berlin (the wife) does really well, as does Eddie Albert (the father) and for a 22 year old beaut youngster Cybill Shepherd is solid also.
Next: this isn't a generic superficial comedy. It's got that peculiar element about it. The humor isn't easy over-the-counter drivel, it's in fact uneasy, almost awkward and difficult to digest. It's about the little annoying details with people, invading personal space, being pathetic without noticing it...in a very real way, all of those things !
Finally, the film holds up very nicely in its one hour forty-five minute frame, with not one moment too many or too few, has a well thought out structure to it that isn't obvious at first, and there's this sort of itchy, awkward anti-morality morality at the end of it that is just as weirdly charming and anti-heroic as its main character.
8/10.