The Vartabedian Conundrum - S2-E10
Continuity mistake: When Leonard, Raj and Howard are talking about Leonard's new trousers, the items on the tray behind Howard keep changing.
The Classified Materials Turbulence - S2-E22
Continuity mistake: When Raj is going through the ideas on what would work to fix the toilet, Sheldon's hand is not near his face, but when Howard talks about moving to Israel, Sheldon's hand is up by his face.
The Monopolar Expedition - S2-E23
Continuity mistake: When Penny finds out about the expedition, Sheldon starts to walk to his apartment. Camera cuts to Leonard in the apartment for five seconds and then to Penny in the doorway. Behind her, you can see Sheldon walking to the apartment still. Since he was halfway to start with, he should be in the apartment by now. (00:10:35)
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