Obsolete "SaveAs3" works but the current version IModelDocExtension::SaveAs doesn't!

I have noticed that the API Help documentation may not be up-to-date.

For example, I was trying to export an open model into one of the standard

file types (e.g., .igs) using IModelDocExtension::SaveAs, which supposedly

supersedes IModelDoc2  Interface : SaveAs3

But, unfortunately, the new function doesn't do what it is intended to!

Are there similar instances that anyone else has encountered and which

a developer ought to be aware of?

Thanks.

(FYI: I coded the above example in C++)

SolidworksApi macros