Have you forgotten that during the first episode with shampoo there was 
a flashback to the Golden pair episode even though it hadn't aired yet?  This is 
because in the manga shampoo's first appearance was at the end of the golden 
pair story, and the TV show planed to show the golden pair episodes first only 
to bump them in favor of the Shampoo episodes.  Origionally the Golden Pair 
episodes were phased into the Second season just after the whole colougne 
storyline, but everyone knew they were supposed to have preceded shampoo's 
arival which is why Viz reordered them into the first shows of the second tape 
series.