> Basically everywhere unless the params are obvious (max(a;b) is a good example)

This isn't so much "obvious" as "irrelevant"; the arguments to max are all exactly equivalent -- their order can't affect the result.

Expanding on the point a little further, it would be normal from certain mathematical perspectives to see max as a unary function, mapping an unordered (multi)set to the set's maximum element. With one argument, order can't matter because only one order is possible.