hi Dave,
you know that i've been around a rotor design.
I went to the conclusion, after some tries, that the double joint or cvj is an interesting design , i plan to investigate a little more on that seriously.
I have tried flexible parts and finally went to a CVJ naturally, you were right, it has a lot of advantages.
do you mind if a have a look at your sketches ? or are they protected ?
I thinh that the advantage of this design is not to avoid flap hinges but, precisely to have flap hinges perfectly aligned with the disk normal and lead lag hinges aligned with the blades path, avoiding the scissors effect and allowing the disk CoG to be always aligned correctly and stable ( no vibes).
I thinbk also that your design has a big interest with 4 blades , the rotor could be considered as a 2 bladed teetering rotor with a stabilizator (the other 2 blades).
Thanks