Not from what I know of how quality tubes are made. The machinery is extremely expensive, way more expensive than some custom cue maker could ever afford or justify in their small scale production. Then you have the thin walled wood core that follows a varying diameter carbon shaft I think. Just not going to happen by some small time cue maker.
I doubt even McDermott makes their own carbon shafts, I'm sure Jacoby doesn't also, then there is the issue of the thin walled wood plug if it is full length as they seem to show. Just not happening on a small custom maker.
Making a wrap for a jet ski that goes over a form is a totally different thing than a small carbon tube. not only do the tubes have to be made so that they have an even flex, but also have to be sanded uniform, then you have the wood plug, just not happening in someone's garage and for a small quantity.
While I agree to a certain extent, it would not surprise me if someone could build a competitive shaft out of their workshop. Something like the Longoni shaft that does not have a seam would be more difficult, but a standard carbon tubed shaft could be done. Would it be worth while cost wise? Probably not as carbon blanks are so cheap from overseas.
The jet ski was was not just a wrap. It was a complete carbon hull/hood combo made from scratch. It was not a copy, but their own deign. Also, keep in mind that they started making them in 2012, and there is a ton more technology available today then back then. Neither of them had a composite background either, one dude sold insurance and the other was an Army guy. The finished products were impressive to say the least...especially considering I would not let either of them change a spark plug in my ski haha.