A Case Against Currying - emih.com

What benefit does drawing a distinction between parameter list and single-parameter tuple style bring?

I'm failing to see how they're not isomorphic.

The tuple style can't be curried (in Haskell).

That's not what I'm talking about.

The article draws a three way distinction between curried style (à la Haskell), tuples and parameter list.

I'm talking about the distinction it claims exists between the latter two.