My take is that most Joss cues are custom built from a limited number (10-20) of cataloged designs that changed periodically. That was fairly common practice among cuemakers who are never questioned about custom vs, production.
My Joss is 36 years old. I was the person who ordered it. In those days, if you wanted a Mali, you bought one of the cues in the showcase. If you wanted a Joss, you ordered it built to your specs (style, weight, shaft thickness, and a few other options). A few years back, I took my Joss to SBE just to show Dan that the care he put into building a solid cue was worth the effort. Mine is still dead straight and plays like it did in 1985 (as best as I can recall).