I meant that sometimes the borders are something like identifier of particular author - like those on photographs of famous Czech photographer Bohdan Holomicek (and fstop photographer Martin Slavik), who's using old Meopta enlarger with manually modified mask of 35mm negative carrier. And maybe one of the reasons to let them on papers/scans (although we could remove them by paper holder or in postprocess) is their meaning that the photograph is enlargement of full frame, not cut-out.

I only want to say that sometimes borders are "signature" of the author - I don't know whether Milan Ulrich is enlarging all of his photographs on papers with large white borders, but he could - and I always try to focus more on content, than on borders (except the borders with stupid photoshop-made signatures, bevels or fake film borders on digital photographs).