> The return type thing was just an example to show that you care about return types regardless of static typing, not that you care about return types during every act of programming.

If we both agree that you do not need to care about types during every act of programming, then lets follow that thread and see where it leads. When do you need to care about types, and how big portion of a programmers time is spent on thinking about types?

My own expensive provides the answer "rarely" and "as little as possible". The few times I do care about types is when interacting with third-party functions, and in those cases I read the manual to figure out what their functions are returning and what I can expect to use. I do not however write test that verify that a function that is documented to return a string actually do return a string (or expect my compiler to do it for me). If the documentation is incorrect then I treat that as a bug, just as if it was a logic bug.

It would however be interesting to hear how much others spend time on it, and in what kind of acts of programming.