The world of online Chastity/FLR resources is considerable. So far as I know -- and I could easily be overlooking something -- there is nobody keeping track of, categorizing, summarizing, and commenting on all this activity, at least within the English-speaking world. There used to be a site (whose name I have forgotten) that did this, but it died. It would be great if someone somehow could replace it. I would be happy to pay a membership fee (I am thinking of about $35/yr) for this service.
I have seen this article, but can't access it? Talking about resources... https://www.chastitymansion.com/forums/index.php?articles/keyholding-methods.1/ Although what exactly do you mean by resources? Definitive guides on measuring? tumbex captions collections? Personal stories?
Are you referring to Altairboy's site? It used to be quite active until a law change with online images frightened the owner into taking all the images off. http://tpe.serve101.org/altarboy/newstuff.php