JW;

You're good here; There are a lot of 12 stringers on this forum and many carbon fiber enthusiasts actually own a wooden guitar or two.

As to your question. I'm not the best source of information regarding 12 string guitars, but I've owned a few and I have played them as six string instruments. Normally I play nylon string guitars so I am used to a wider nut and found the 12 string works as a 6.

My only reservation would be the possible loss of resonance. A 12 string is designed to take a lot of pressure and I suspect that when you remove 6 of those strings the remaining 6 may not resonate well. This is just a suspicion on my part.

While you are here, you might want to take a look at the Emerald Guitar site and check out the 12 string guitars available in carbon fiber. In any event, good luck with your exploration.