The One With The Lesbian Wedding - S2-E11
Audio problem: During the lesbian wedding, whenever we see a shot of Carol and Susan while the minister is talking, her mouth is not moving. (00:18:35)
The One With The Lesbian Wedding - S2-E11
Continuity mistake: In the beginning when Carol and Susan tell Ross that they are getting married. Ben changes from a blonde baby to a brunette baby.
The One With The Lesbian Wedding - S2-E11
Continuity mistake: 12 hours before the wedding, Monica asks Joey to speed it up. Here she is stirring a bowl. In the next few seconds you can see Monica holding some condiments in her hand. After Phoebe answers, Monica is stirring again and the condiments are nowhere to be seen.
The One With The Lesbian Wedding - S2-E11
Revealing mistake: The first time we see Rachel's mom in the coffee house, Rachel puts her coat on the hook by the door. When she does this the wall visibly shakes.
Answer: The statements that she's contradicting (that it is common, it happens to every guy, and it's not a big deal), are the things that a woman commonly says to a man who is suffering from erectile difficulty, typically to assuage his bruised ego. However, most men do not believe that these statements are true, as evidenced by Chandler's outburst. He's so caught up in the proof that women are lying about it that he gives himself away.
Rooster of Doom