yes. at some point layers and layers of mastik will not make a bond stronger, it will still sheer between the layers. Belgian tape in addition to building up the center has its own adhesive along with the backing, and it seems like the mastik soaks into the tape creating a better joint. With a normal tubular glued with just mastik, you only want it to be sticky enough so that it holds during corner say on the road and still be able to be removed by hand in case you need to do a roadside swap with a spare tubular. This simply wouldn't be possible with a tire glued with belgian tape. Generally to remove a CX tubular you have to cut it off, or use a flathead to get under the tape enough to get a wooden dowel or some other object to leverage the tire off. I've never seen anyone be able to remove a recently glued CX tubular by hand like you see with road tubulars glued with just mastik.