Lol! Thanks Al! As long as she doesn't board a plane to search for her Canadian roots, I think I'll be okay!

However, it's interesting that Mr. Kaman didn't settle for X-bracing after all the different patterns attempted on production guitars upto that point (Damon67's "VT-9" Deluxe Balladeer earlier in the thread is really interesting). It only hit me recently how significant an engineering feat the A-brace is. I may be wrong, but a chronological review of Ovation bracing patterns suggests that the A-brace became the standard on which the Quintad bracing for the Adamas and the Elites were developed. I just can't say enough about the Quintad bracing on my 1678 and 1868 - incredibly responsive and durable. Can I hear a, "Bye, bye cross-bracing!" from anybody? It's also interesting that peripheral patterns like the K-5 (that seem theoretically sound) were done away with. Really interesting stuff!

I am quite conviced about the advatages of any non-croos-bracing. The sound and durability of Adamas or Elite guitars proof it. That´s why I some years ago choose a bracing like this when I decided to have a custom 12string guitar built for me from my favourite luthier Ernie Rissmann. He built a short-scale 12fret cutaway guitar with a deep body and a spanish body size, with offset soundholes. The bracing is even thinner than that of Ovation 12string guitars and has only one (curved!) transversal brace instead of 2 straight ones. The result is such a powerful guitar that I later had a nylonstring and a 6-string made with the same features. These 3 guitars can easily outplay any other of my guitars.
Here are pics of the 12 string braces, the Nylonstring and the 6-steelstring:

The Ovation A braced guitar have a wonderful sound, though, but the bracing pattern has a weak spot: there is no complete brace through the whole lenght of the top, and the metal reinforcements on that point are too soft and not very elegant..my parlor 12 string guitar´s top almost broke down in the middle, this would not have happened if there woud habe been 2 supending long braces instead. The Gibson Mark bracing of the 70´s  had the same problem, great sounding but the tops tended to move too much. I had one...Besides that continuosly fixed long brace surely will perform better than a 3-piece patchwork. See above.
And you can play much lighter strings on a guitar with fan bracing than with X-bracing, with same results. But..does the fan bracing only make sense when you do not use a center soundhole? Did anyone try to make a dreadnought-body guitar with a stronger fan bracing?? Why not, the center-soundhole CL sound great...

Hi DetlefMichel! It's always very cool to get your take on things here at the OFC. Thanks for sharing pictures of your Rissman guitars! Just fabulous. I don't think you've ever uploaded any videos of those! Would love to hear them all, but especially that nylon stringer! If you get a chance, please upload a video or two! I'm already subscribed to your channel so even if you don't post it here, I'll definitely see it.

I'm no engineer, so I need to be careful about over simplification of complex acoustic constructions, but I'm in total agreement with you about unnecessary cross-bracings under the bridge area. In reality, the bridge itself acts like a short cross-brace anyway; and the simplicity of the Quintad design is just so elegant.

Now see, that's just it. My 1612 rebuilt by Dan Savage has a K-5 bracing pattern that does exactly what you say. Long braces along the length of the guitar on both sides of the sound hole like this (pre-rebuild photo);

You'd think this would work better than an A-brace, but the K-5 was short-lived and eventually discontinued. My 1612 is completely torrefied, and the closest thing to a deep bowl A-braced guitar I have is my 97C (which I do love), but it's a 12-Fretter. One of my 1861s and my 5986 is A-braced, but they're both SSBs and are not comparable. However, when comparing just the bracing patterns (a lot of subtle differences, but...), the A-brace has a bit of a "tighter waist" where the lower cross-brace meets the lateral braces;

Seems like that would allow the top to resonate just a bit more. All 7 of the lateral braces on the A-brace extend close to the butt end of the guitar whereas only 5 out of the 7 lateral braces extend down toward the butt end on the K-5. Frankly, even if I had a directly comparable guitar, I get the feeling, I wouldn't be able to tell an A-braced guitar from a K-5 braced guitar, but with the sensitivity of the equipment that Mr. Kaman was using, these little physical geometric differences could have looked massive? The Quintad bracing is every bit as interesting...

The area on the bass side of the guitar is a little more restricted and the braces fan out a little bit more than an A-brace, but the all lateral bracing construction must contribute to a more unified movement of the soundboard which would enable the top to "pump-oout" more resonance so to speak. Anyway, thanks for chimming in with your insights and please share some sound bites of those beautiful Rissman guitars when you have time!