I can kinda see the point he was driving at. I think the argument was basically centred around the disadvantage of inheritance - if you're not careful, or if you inherit too many times to keep extending functionality you can end up with a bloated mess of a class with a load of redundant features and lack of cohesion.
His analogy works if you consider that, once the rocket has burned the fuel in a segment, the segment becomes redundant and therefore dead-weight. The rocket can jettison the segment, but I don't think it's possible to exclude sections of a class you don't want to inherit (although correct me if I'm wrong, because it sounds useful).
