Especially this part, from toward the beginning:

> Before I get into the details of what Y actually is, I'd like to address the question of why you, as a programmer, should bother to learn about it. To be honest, there aren't a lot of good nuts-and-bolts practical reasons for learning about Y. Even though it does have a few practical applications, for the most part it's mainly of interest to computer language theorists.

The article goes on to explain why you should learn it, anyway, but, still, it's not like monads and Haskell. Despite the concept's intellectual cachet, you don't need to understand it to be an effective lisper. That said, this opinion is mine and mine alone, and stands in direct contradiction to the sentiment expressed in the following paragraph.