I think that ad was just something left over at Saachi's and they thought what the heck lets offer it to Cadbury.
Yes people are talking about it but no one remembers its for chocolate - fatal mistake, a bit like the Leonard Rossiter & Joan Collins Cinzano ads in the 80's, they won loads of awards but no one could remember the brand - was it Martini or Campari or Cinzano? You have to get the brand name into the hook otherwise it's a total waste of money.
Tango ads got it spot on