I disagree. His point is not merely that Haskell advocates cannot clearly explain simple interfaces like Monad (let's be honest here; this is more about Haskell

I disagree. His point is not merely that Haskell advocates cannot clearly explain simple interfaces like Monad (let's be honest here; this is more about Haskell folks being too researchy, and not being better skilled in the dog-and-pony-show environment of "practical" marketing), but that the lack of skill in clear explanation is due to a reluctance to admit that "Haskell needs the ability to do imperative things in order to be useful". The thing to "get" about Monads are that they are a means to describe imperative things going on, in a way that blends in with not necessarily imperative things. Which is part of why it's so tough to explain them - we're all talking past each other regarding what "the point" of using Monads are. The point to them in Haskell is mainly twofold: 1) Haskell users can use a Monad to describe net access, DB access, file access, and other "once done, the results are out of your control" effects in the same way as describing using (Writer) computations that keep a log of what's being done, (Error) exceptions, (Reader) environment variables, (List) functions with multiple - or no - results, and more. It's really easy...and kind of mind-blowingly complex, all at the same time.