Paul Winfield should have been nominated Supporting Actor
Nominating him for best leading actor wasn't appropriate. After David visits his father in lockup, Martin isn't in the film for 40 minutes (1hr 45min film), except for the short dream sequence. David was the focus of the story, not Martin, if anything the son should have been nominated for best actor.
They bumped Al Pacino in The Godfather down to a supporting actor nomination, when he was clearly the lead of the film (both in screen time and the focal character). I suppose they did that since Michael Caine and Laurence Olivier were both nominated for best actor for Sleuth, that they didn't want to have another dual best actor nomination with The Godfather, so they nominated Brando for lead and Pacino for supporting.
Religion should be made fun of. If I believed that stuff, I'd keep it to myself. -Larry David