that's true, but that's also what makes it so funny in fact i think he's just so distracted!! 2 episodes come to my mind and i'm sure a lot of people out there will find others The Cafe, at the beginning when Jerry and George are in the street, George talking about his girlfriend who wants him to take an IQ test The Pez Dispenser, at the beginning when george is so enthusiastic about his pianist girlfriend, and Jerry didnt listenned!!
it happens with Elaine too, i remember in the episode The Stall, at Monk's when elaine tells Jerry she couls maybe discover love thru her boyfriend's accident (pretty boy Tony)