Go to the part where Rachel tells Phoebe she's going to London to tell Ross she loves him. When she comes out of her room she is wearing a sweater. When the camera cuts back to her she's not. When she's hanging her coat on her luggage there's that sweater again. When it cuts back she's not. When she finally leaves she's wearing the sweater. How could this happen? I can't believe someone didn't catch it.