It takes a while to master reading math notation or music notation. Mastering reading Haskell isn't that different. Some people are served well enough by just learning guitar tabs, others feel they're better off mastering music notation.
For the record, I can read both standard notation music and guitar tabs. I'm fairly competent at Haskell have written APL/J/K derivative languages for a living. "Mastering reading Haskell" certainly has to do with a lack of "go to this page on the wiki/hoogle/haddock and you can read the meaning and idiomatic usage of the 95% most common operators", not a lack of conceptual grasp of anything difficult.
It's in no way comparable to learning math notation or music notation.
There's a few things, like fixity declarations, that make parsing Haskell not quite as easy as it could be.
Implementing exactly Haskell's rule for indentation is incredibly hard. In fact, no known Haskell compiler gets it right.
https://mail.haskell.org/pipermail/haskell-cafe/2009-April/0...