I'm trying to imagine my disappointment if the merit of one of my images hinges on the peculiarities of framing with a white matte and the placement of a small black border...
I wouldn't say "hinges," Oscar, as presentation matters. Ultimately, a print is rarely seen in isolation (at least by the public). A print is one thing, and the print on the wall quite another. The peculiarities of framing are quite important. Knowing that you are from Holland, I'll offer this anecdotal evidence: when visiting Van Gogh museum, I bought two books. One was about his work (duh!) and the other was about the art of framing through centuries. Artists themselves were often quite involved and picky about how to frame their work.