That's my point. I want that you publish what your API actually does. I've written programs which MSDN said wouldn't work. Clearly a bug in MSDN. Did MS not know? Or is it to trip up wine?
You may not understand something important about Windows API. Let me explain.
There's the documented, public functionality that Windows implements and wants all the applications to adhere to. This should be documented and it is.
Then there's the functionality that Microsoft had to implement behind the scenes because some important application used it in an incorrect way or it worked by accident. They didn't want that application to break with a new release of Windows. Now Microsoft doesn't want new applications to use this, so they don't document it. I think that is absolutely correct.
MSDN API documentation is meant for people that write applications the way Microsoft wants the applications written.
Wine isn't an application. They want to emulate what Windows does. The API documentation is not for that purpose and it shouldn't be.
That being said, there are APIs in Windows that are secret and undocumented. Those should not be used by applications. Windows isn't open source. Accept it.
That's not the purpose of MSDN documentation though.