Do you know of any person that made a decision based on the slogan contents? It was an obvious joke. I've seen people claiming to avoid a language that posts a joke on the front page (honestly, appeasing to those people were a sure way to add those costs the slogan is about), but never because of the message.
Anyway, removing the parenthesis makes it clear that the operations are associative. Otherwise the phrase would be wrong, and Haskell developers really dislike that kind of wrong.
I think you took the wrong message from my message.
I was saying that the Haskell people were unapologetic (and obviously tongue-in-cheek)... and that one perhaps shouldn't expect massive commercial success when the people in charge obviously weren't going for that.
Anyway, removing the parenthesis makes it clear that the operations are associative. Otherwise the phrase would be wrong, and Haskell developers really dislike that kind of wrong.