The Vengeance Formulation - S3-E9
Continuity mistake: When Howard is proposing to Bernadette she is holding a tray with two glasses on it. The glasses are next to each other, side by side for two shots of her. Then in the third shot the glasses move so one is behind the other. Then in the fourth shot they are side by side again.
The Vengeance Formulation - S3-E9
Continuity mistake: When Leonerd sits on the whoopie cushion, he picks it up and it has creases in. Camera changes and the creases have changed.
The Einstein Approximation - S3-E14
Continuity mistake: When Sheldon is looking for another job, the woman is holding a piece of yellow paper up. Camera cuts and she is no longer holding the piece of paper.
The Einstein Approximation - S3-E14
Continuity mistake: When Sheldon is playing in the ball pit and Leonard is trying to coax him out the position of the black netting of the ball pit alternates between being and not being wrapped around the yellow entrance pillars.
The Large Hadron Collision - S3-E15
Continuity mistake: Penny asks Sheldon if the roommate agreement contains something about girlfriends, which Sheldon dismisses as unrealistic. However, it was revealed in season 2 that there is a cohabitation rider. This was revealed when Sheldon asserted that Leonard's girlfriend, Stephanie, was officially living with them.
The Precious Fragmentation - S3-E17
Continuity mistake: At the cheesecake factory, the necklace is wrapped around his middle and ring fingers, then in the next shot, he is just holding it. (00:08:00)
The Precious Fragmentation - S3-E17
Continuity mistake: When eating at the Cheesecake Factory, the position of Raj's hamburger bun changes from shot to shot. (01:06:00 - 02:07:00)
The Precious Fragmentation - S3-E17
Continuity mistake: When Sheldon sneaks into Leonard's bedroom while Leonard and Penny are sleeping, Penny has her arms out over the blanket and Leonard has his on his pillow in front of his face. When Sheldon leans over Penny only her hands are on top of the covers and Leonard's are tucked under his pillow.
The Spaghetti Catalyst - S3-E20
Continuity mistake: When Raj and Leonard are sitting on the couch, Leonard is holding Watchmen and Lost in Space in his left hand and Young Sherlock Holmes in his right. In the very next shot when Leonard turns his head after Raj speaks, Watchmen has disappeared.
The Plimpton Stimulation - S3-E21
Continuity mistake: When Sheldon, Penny, and Leonard are discussing Leonard's tryst with Dr. Plimpton, Penny pinches the bridge of her nose with her right hand. The shot changes and Penny brings her left hand down from her face.
The Robotic Manipulation - S4-E1
Continuity mistake: At the start, as Howard says "And finally my kung pow chicken" the robot arm is level with the top of the bag. Camera cuts and it's reaching to the bottom of the bag. (00:00:15)
The Robotic Manipulation - S4-E1
Continuity mistake: When driving to the date, the cars behind Penny's change place instantly. For example a 4x4 becomes 3 cars, which become 1 car in the space of 3 seconds. (00:09:10)
The Robotic Manipulation - S4-E1
Continuity mistake: When Penny says "let's just finish our dinners" she raises her fork twice. (00:16:45)
The Robotic Manipulation - S4-E1
Continuity mistake: The lemon wedge in Amy's water flips back and forth throughout the dinner scene. (00:17:00)
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The Robotic Manipulation - S4-E1
Continuity mistake: In the ER, the glasses around the nurse's neck move instantly without her touching them. They go from angled to straight instantly. (00:17:45)
The Hot Troll Deviation - S4-E4
Continuity mistake: When George Takei and Katee leave Howard's bedroom, in one shot Howard is clasping his hands together, in an instant they are spread out completely. With no time to move them. (00:04:25)
The Hot Troll Deviation - S4-E4
Continuity mistake: When Leonard and Howard are talking at the University, Leonard says "Oh my god you ran over a hobo!" when he does so Howard is not holding his fork, camera cuts and he suddenly has his fork in his hand. (00:05:15)
The Hot Troll Deviation - S4-E4
Continuity mistake: When Sheldon and Raj are arguing about having a desk in Sheldon's office, Sheldon's bottle of water keeps rotating without anyone touching it - take note of the label. The level of water in Sheldon's drink also keeps changing between shots. (00:06:20)
The Hot Troll Deviation - S4-E4
Continuity mistake: When Howard and Bernadette are talking in the Cheesecake Factory, her apron that she puts on the table is constantly changing position. (00:12:30)
The Irish Pub Formulation - S4-E6
Continuity mistake: As Raj, Howard and Sheldon are sitting at the table discussing leaving Priya alone while Leonard and Priya are away from the table, a water bottle sitting in front of Raj moves back and forth between his tray and Leonard's tray.
Chosen answer: It does. The variable cleanliness of the cab and the habit of taxi drivers to engage customers in small talk would be too much for Sheldon to handle, and not an option for him.
Captain Defenestrator