Continuity mistake: When Jerry's sitting with George in the hospital talking about George's jacket, as Jerry says "no, I tried it on, it fits good", he's gesturing with his left hand, which he then puts in his lap. From the reverse angle though, his left hand's still raised, then he lowers it again.
Revealing mistake: After the scene in which Elaine tells Jerry about her confrontation with the "head-nodding" man, and before the scene where George swallows a fly, the scene cuts to a shot of the exterior of Monk's café. The actual, real-life restaurant used for exterior purposes is named "Tom's Restaurant," and the "m's" in "Tom's" can be seen during this five-second shot. (00:23:00)
Continuity mistake: Jerry says he has never seen an episode of I Love Lucy in his life, then pops the cork on the wine bottle. Then it cuts to the lady and she asks, "Is there anything else about you I should know?" and the wine bottle is still on the table, corked. Then it cuts back to Jerry, and the bottle is still in his hand uncorked. (00:11:40)
Continuity mistake: Elaine is by the table with the 6 people and start whispering through her teeth her proposal to cheat at the dare, The Old Man puts his hand on his wife's hand in one shot, but he's simply gesturing close to her in the next. And that woman is holding the fork in hand or not, depending from the angle. (00:07:20)
Continuity mistake: Jerry is explaining to Elaine what to do for eggroll dare. She listens and uncrosses her arms. When he says the words "I'll give you 50 bucks" there's a cut, and Elaine's arms are again folded. It happens again right after when Jerry says she'll give the people at the table a story to tell. (00:06:10)
Continuity mistake: After the 4 people bypass Jerry and Elaine, George is trying to get the attention of the man at the phone, who just turns the other way. George angrily licks his lip and leans against the corner. Cut to Jerry, and in the background George is repeating the action of leaning, in a different way from before. (00:03:50)
Other mistake: The previous episode "The Deal", was supposed to be the season (and possibly series) finale, however it was aired out of order. Therefore in this episode and the next without explanation Jerry and Elaine are not romantically involved anymore, and Kramer pitches cable to Jerry as if he never had it before, mentioning "The naked channel" that was sorta the triggering factor of "The Deal" 's plot.
Other mistake: When George is taking off his sweater revealing the chocolate-smeared shirt, a woman in the background hilariously stares, looks down at the shirt and then eyerolls. She is behind him, though, and can't possibly have seen the stain. The shirt looks fine from the other angles. (00:16:30)
Continuity mistake: Kramer tries to stop Jerry from running towards the door. "Agent Stone" in the following shot has his badge in the left hand (was in the right earlier) and reaches with the right for his gun under The Jacket. But there's another shot, with cornflakes and other things being blown up by bullets, when Stone is still showing his ID in the right hand. (00:09:00)