For what it's worth, I've worked as a professional Haskell programmer at multiple companies and have been writing Haskell for more than a decade, and I still have trouble reading code written in that style. I usually end up decomposing it at a REPL so I can look at the types of intermediate parts of the program.

(In practice, most—although not all, admittedly—of the Haskell codebases I've worked with tended to be a lot less dense than the occasional combinator-heavy sample code you see in blog posts and comments.)