- Jay (Romany Malco) is a classic Gut character, advising Andy to be animalistic, “All you doing is using your instinct. That's it. Tackle the gazelle.”
- David (Paul Rudd) is all-Heart, still hung up on an old relationship and constantly imploring Andy to pursue old-fashioned romance.
- Cal (Seth Rogen) as Head is the least obvious of these three, but, like many Head characters, he is both a would-be novelist (this is more clear in the extended version) and the Jewish member of the group. His advice is all about head-games, employing a strategic “ask questions” method.
It’s only after he’s tried each version on its own and found each one wanting that he realizes that he has to integrate them into one method, and thereby integrate himself into a whole three-dimensional person, surpassing each of his former mentors.
In the commentary, Apatow cheerily points out that, though he and Carrel are the only credited writers, almost every scene in the finished movie was not in the original script, and instead came from jokes pitched by various actors in the movie, and even by some who aren’t in the movie. For instance, he keeps crediting gags to, of all people, Garry Shandling, One of Shandling’s suggestion was, “Once the virgin has sex, it has to be better than all the other guys’ sex”: This led to the wonderful finale in which Andy can only describe his deflowering by leading a jubilant performance of “Age of Aquarius”.
Shandling’s point, it seems to me, is that Andy has combined his friends’ incomplete parts into one whole, and achieved a level of fully-human experience that is denied to them.