[cle]

Not only do you need to remember the arity, but the order as well, which is IMO worse (at least a type system can protect you from arity mistakes). If your function is not commutative for adjacent arguments of the same type, you're skipping through a minefield if you rely on currying.

[ajanuary]

How is that any different from having to remember the argument order in normal function application?

[cle]

Conceptually it's not that different. Practically, it's pretty different because you're effectively fragmenting a single function application across your codebase, making it harder to reason about and more likely to make ordering mistakes.