Actually, with DynaBeads, the correct phrase would be "in my experience". I fortunately have no experience with the combination of beads and plugs, so yes, that part is "in my opinion". Somehow, "no doubt" did not trigger the obviously implied "in my opinion" you mention. My reading skills must be slipping.
Your other misapprehension is that the beads are continually rolling around the tire. Once the bike/tire is up to speed, they are for the most part stable in their location. Since the plug slightly alters the balance point of the wheel/tire, the beads' location will likely shift somewhat from the pre-puncture pattern.
Cheers.