I don't think the program does that, if I understand your post. A more accurate name might b "exclude what you don't use." It doesn't add in chained includes, it just lets you know about superfluous includes.
I was pretty sure it does that, since people in projects I work on use it. To make sure that I'm correct, I just ran it on some code I work on, and indeed, it wants to add (...c should add these lines ... ) implementation details to a lot of sourcefiles.
I guess this can be a problem for cross platform code, yes?
Or even compatability with different versions of the same compiler, runtime or libraries.