I was just talking with Jerry and Michael yesterday about quads. I played with them a BUNCH and just could not get them to work. Jerry was telling me that he has almost 3 years of R&D into them and is just now getting them dialed in. As a manufacturer Jerry has access to all sorts of resources that I don't, plus 40 years more experience
I think that some really savvy hydrodynamic surf guru will work out the formula - like Jerry, but I sure couldn't.
I've also talked with a number of professionals - Eric Roush says that quads are the best thing since sliced bread. Rich Sanders and Wil Jobson (the originator of the Twinzer) say that for the small waves we work with the Twinzer set up is preferable to a quad...so who knows.
The bottom line though is that James preferred this C-5 / twinzer setup to any of the true Twinzer or Quad setups. We generate drive and pop through the planshape and the internal structure, so we don't have to rely so heavily on the fins. If you look at all the pictures of James' aerials using this board, basically all are done with a single pump up and into the wake. He is able to generate the same terminal velocity as a quad in about 2 less pumps. With a longer usable pocket, he can develop considerably more speed.
This shorter or more closely grouped fin pod allows James to still do his surface rotational tricks which was the biggest shortcoming on all of the quads that we tested/made.