It's not really a particularly new idea. Back in 1984 a group of engineers in the Engineering Resins Department of Amoco Chemicals Corp. developed a variety of plastic-based internal engine components that included things like rocker arms, bucket tappets, piston skirts, valve stems, gears and pulleys, etc. The most interesting for this discussion were connecting rods made of woven graphite fiber (aka carbon fiber) fabric impregnated with a high temperature polyamide-imide resin (trade name TORLON), compacted under temperature and pressure into plate, from which the rods were machined. They ran the parts, including the rods, in a Lola T-616 IMSA GT car, and managed to complete at least one of the races successfully, running for 2.5 hours in excess of 8500 rpm. That's all from a 1985 SAE paper, so I don't know how much further they went with the project, but there is probably some reason we haven't seen any of the products showing up in mainstream cars or bikes.
I recall seeing at least one other attempt at making connecting rods machined from carbon fiber plate, but don't have any info on it at hand.
FWIW, although this stuff is interesting, I think the most appropriate rods for our Nortons are either the stock aluminum/steel items or quality (like Carrillo) steel rods. The choice depends on the application. I like the steel rods for engines that will be highly stressed (racing or abusive street use), although the stock rods can be so used, as long as they are crack checked and/or replaced regularly. The only other affordable alternative is titanium, and my experience with them is that you don't really get a significant enough reduction in reciprocating weight to make them worth the extra cost. The design that would get my vote would be an aluminum/ceramic MMC material, but I don't see that happening at any reasonable cost in my lifetime.
Not much practical info for most Commando owners here, but still fascinating to watch new technology developments applied to IC engines.
Ken