I think you're confusing the act of receiving information/understanding about an experience with the experience itself.

Re: the joke example, I think that one would get tired of hearing a joke too many times, and that's what the dissection is equivalent to, because you keep hearing it in your head; but if you already get the joke, the dissection is not really adding to your understanding. If you didn't get the joke, you will probably receive a twinge of enjoyment at the moment when you finally do understand. If you don't understand a joke, I don't think you can get warm fuzzies from it.

With hormones, again I think that being explicitly reminded of the role of hormones in physical attraction while experiencing physical attraction reduces warm fuzzies only because it's distracting you from the source of the warm fuzzies and making you feel self-conscious. On the other hand, knowing more about the role of hormones should not generally distract you from your physical attraction; instead you could use it to tada get more warm fuzzies.