Corrected entry: Sam's friend Eddie shows up and says they made a bet a year ago while drinking tequila. This isn't possible, prior to his "falling off the wagon" when Diane left he hadn't had a drink in about five years (he told Diane 3 years in the pilot episode) and a year hadn't passed since he's fallen off the wagon when Diane left.
Corrected entry: As Sam tells Diane about the guy from Baltimore, the camera starts to pan around the bar. Just as the camera goes past the women's bathroom, the door starts to open. The door then closes itself in an instant frame. (00:22:40)
Correction: A few seconds must have been edited from the version you watched. When I watched it two women come out of the bathroom and the door closes normally.
I noticed this mistake on a Region 2 DVD box set from the UK. From what I seen, an editing blip occurs where a couple frames of film are repeated just as the door starts to open. This editing error may have been corrected on other DVDs and television broadcasts, but I definitely remember seeing this on the DVD that I own of it.
Rebound (2) - S3-E2
Corrected entry: When Carla asks Frasier if he's "taken a good look at everyone else", the camera pans to the bar patrons. Dianne is sitting at the bar smiling. She wouldn't be drinking at Cheers because of her recent falling out with Sam. Dianne then comes in the bar looking for Frasier a minute later wearing different clothing. (00:06:50)
Correction: Just watched the scene and while the person has a slight resemblance to Diane, this is a different actor.
The Sam in the Gray Flannel Suit - S6-E20
Corrected entry: Sam and Rebecca are in his office talking and he is wearing a tan suit with brown shoes. He leaves in a hurry to go into a sales meeting in Evan's office, and he comes in wearing a dark suit with dark shoes.
Corrected entry: When Sam and Diane are alone in the hospital room, he tries to make the room more romantic by dimming the lights and moving a table so that no-one can get in the door, however when Diane doesn't go for it and goes to leave, the table is back in its original position, and no one went near it.
The Last Picture Show - S11-E18
Corrected entry: In this episode, it's stated that Sam bought the bar from Gus O'Malley. However in "Sam's Women" (season 1), when a man comes in looking for "Gus," Norm says that Gus was two owners ago.
Correction: Who's to say that there wasn't a Gus who owned the bar at the time in question? Norm is a heroic beer drinker - he could easily be drunk enough to confuse two people with the same forename.
Corrected entry: When Sam is fantasizing about what life would be like with Diane when they are old and living in the house, when Diane serves the tea to Sam and the regulars who stop by, there is no steam rising from the cups to prove that the tea is hot.
Correction: You don't always see this in real life, and it might be hard to capture on camera, anyway.
Corrected entry: When Wally shakes hand goodbye with Norman and Cliff, he said, "Nice meeting you, Cliff". But he can't know Cliff's name - they were never introduced to another and his name was never mentioned. (00:12:40)
Correction: Cliff is a mailman, and he is wearing his namebadge.
No, he's not. There's no nametag on his uniform.
Corrected entry: In this episode, Carla knows Eddie didn't send her the flowers because she said his real name isn't Edward, it's Gee but in the episode when they're married, the priest says, Do you, Edward LeBec take Carla?"
Correction: The priest at the wedding of Prince Charles (the first wedding, that is) got his name wrong - why can't the priest in a small wedding in Boston? Character mistake.
Correction: It's possible that Edward wanted his preferred name spoken at the wedding. He could still use his legal name on the wedding documents, and when he communicates with Carla. I have met people who only want their spouses and closest friends/family to call them by their real name.
Corrected entry: Sam finds out that the song that makes Rebecca melt is "You've Lost That Lovin' Feelin'", but later he plays for her "Unchained Melody" and she reacts as if it were the song.
Correction: "Unchained Melody" is the song Sam played to Rebecca in her apartment when she was drunk and realied she doesn't love Robin. "You've Lost That Lovin' Feelin'" was played in the bar, when the singer came in. If she remembered that, there would be no frame of reference.
Woody For Hire, and Norman of the Apes - S6-E13
Corrected entry: When Woody is making finger sandwiches, Sam tells him that they don't have to be in the shape of fingers (or something along those lines), and Woody replies back "Whatever, Ted". Ted is the actor's name, not the character's name.
Correction: I am a recovering alcoholic, and teetotal, but even I occasionally have a relapse, generally when meeting old drinking buddies. I regret it to hell the next morning, but it happens - to me and to Sam.