Other mistake: Sam tells Rob "Laura could be late because of the rain". Yet neither Sam, Laura, Millie or Clark had any wet clothes, jackets, hats etc. Rob was the only one that had gotten soaking wet. Also when looking into the window he taps on the glass with a white glove (which he didn't have on when he got into her house).
Other mistake: Millie tells Laura (in the USO women's house) "I can't keep a boyfriend" yet she's been "married" to Jerry and they get along somewhat OK.
Fifty-Two, Forty-Five or Work - S5-E13
Other mistake: Right at the beginning of this episode Rob says "9 years ago right in this office... I just came on as head writer 2 months was all... Buddy, Sally and I were sitting at this desk, writing a sketch, and you (Mel) came in with some special news." (so on and so forth with that line.) Rob, Sally and Buddy weren't in "this office" building... Didn't even have the same desk or furniture.
Other mistake: Evan from the insurance company comes over to ask Laura and Rob several questions but not once does he find out any names from the party. But the next day Buddy, Sally, Mel, Jerry and Millie all get really angry because of Rob and his interrogator just assuming that they stole the watch.
Suggested correction: Evans says he had all the preliminary information from Rob's earlier phone call including the names of the party guests.
The Bottom of Mel Cooley's Heart - S5-E19
Other mistake: All the extra people in the back aren't talking. There is one pair of people at the table near the wall behind Rob and Mel that keep glancing at them and look very uncomfortable. (00:11:00 - 00:13:00)
Other mistake: That mirror behind Rob at the hotel in their room has fog (condensation) on it which means that the humidity there in "Mexico" is really really high or it's over 100°F in their room with humidity or unless it was raining inside their room, the window behind the bed is perfectly clear. (Real life that mirror would not be all foggy.) Also Rob, Laura and the hotel guy would have been sweating up a storm if it was really really hot out there. Which it wasn't. (00:13:52)
Buddy Sorrell, Man and Boy - S5-E22
Other mistake: Rob got a new watch for his birthday a few seasons back. Yet he's still wearing his old watch. And also his watch time says it's 3:00. Rob and Sally would still be at work if it was actually 3:00.
Long Night's Journey into Day - S5-E23
Other mistake: Rob tells Jerry to keep calling Rob's house. Jerry says "hello, this is Jerome Helper" yet there was the episode "All About Eavesdropping" where Rob calls Jerry "Gerald."
Long Night's Journey into Day - S5-E23
Other mistake: Millie tells Laura "I never sleep in my house alone!" yet Millie has been home about 2 or 3x by herself. In other episodes. Like when Jerry goes out of town usually.
Love Thy Other Neighbor - S5-E29
Other mistake: Laura tells Rob that Jerry is fixing the fence. Then all of a sudden this banging that sounds like an iron hammer and chisel on cement starts up. If Jerry was actually fixing the fence it would have been the whole time, right when Rib got into the kitchen, not right after Laura told Rob that Jerry was working on the fence.