Evidence that it does work at finding undeclared functions does not contradict the claim that omitting parens in function calls introduces problems.

The main problem is that unary "+" or equivalent must be used in a number of places, and forgetting to do causes bugs. These are not always caught at compile-time, and they can be subtle.

Another problem is misleading error messages.

Three issues from omitted parens came up here and/or on stack-overflow in the last month, but I don't remember them.