I noticed that raw2image() does this and it felt redundant. So I was confused as what is the utility of it, having no historical knowledge about the library. I just started using libraw ( expect more of me around here :) ), so I think there's no point to use old workflows, which will most likely become obsolete soon.
I only wanted to make sure I understand what I am doing. Thank you for your explanation, now it is clear.
As a suggestion: if there would have been a repository for the documentation, I would have done the change myself.