Dear ROL, I was looking up the term "overmat", and I think that, perhaps, I did not fully understand your point, in which case, my apologies. I realise that this term is something that may have changed meaning a good few times, and it may be regional, however AA's The Print (2000 printing, page 156) uses the name "overmat" to describe a bevelled-cut window that is placed over the print with a space around the edges of the print—the same approach, indeed, to the one you have described in your excellent article, using just slightly different terminology. 2nd edition of Way Beyond Monochrome (pages 70–71) goes further, to say that the only difference between an "overmat" for a dry-mounted vs corner-mounted print lies in the size of the opening which either does not or does overlap the edges of the print.
Originally Posted by ROL
On the other hand, the verb "to overmat" is not as popular, it seems. WBM, Kistler, and Hyder, all refer to the creation and assembly of the overmat simply as "matting", but Adams still calls it "overmatting". My Shorter Oxford does not list a verb "to overmat" at all, but even its many descriptions of "to mat" only vaguely refer to what we mean by this term... In all cases, I fully respect your use of the term, and I am thankful for your feedback. I will clarify the captions to the photos in my article.