I agree. In a recent thread at DPreview I argued at length about this. The fact is the little DP Merrills, which are now like ten years old (I just checked, and the DP2 Merrill was announced February 8, 2012), have to process almost as much information as the FFF camera will (45 MP vs 60 MP), and processors have multiplied in speed/capacity since that time (more than doubling). This means they can indeed put a FFF sensor into an fp, with its bigger battery and special heat dissipation capability. They just need to be willing to do it. I don't think they are . . . yet. I think they just want to put the new sensor (when it is finally ready) into a form factor that screams, "I am a flagship camera!" The little fp body doesn't do that. I think they'll put the FFF sensor into the fp about a year or so after they put it into a nice body, which has an integrated viewfinder, with a bigger battery, which has an optional battery grip that can hold two batteries, and that larger camera body with have a dual-processor of some type, so it is significantly faster than any previous camera ever made with a Foveon sensor in it. Since it will be the first L mount camera with an X3 sensor, it will sell reasonably well, I think, and when they put the same sensor into an fp body, I believe many DP series camera owners will finally buy an L mount camera. Sigma has the little lenses available, and while the fp with a lens is not quite as small as a DP Merrill, it will be a faster small camera with an optional electronic vewfinder, which is something that has never existed in the world of Foveon sensors. It will still be significantly smaller than a full-sized camera, and it will be full-frame, so it will have an excuse for being bigger than the DP Merrills.
BTW, for those who doubt that the fp can handle the FFF sensor, please tell me how the fp L can handle a 60 MP sensor? It seems to do it just fine, because I don't see a lot of complaints out there about how slow that camera operates. It's getting old now, and any newer model of fp will no doubt get a new, much faster processor (i.e. something 50% faster or even twice as fast as the one in the fp L). Now I know that Bayer pattern CFA cameras have the advantage of being able to take advantage of all sorts of circuitry that has been embedded into the modern processors that are made for compact cameras and smart-phones, but don't forget that the little DP2 Merrill worked just fine (though slowly) with a processor that was made for the world of CFA cameras too. That was more than ten years ago now, and today Sigma can easily get a processor that is more than twice as fast as that processor from the little DP2 Merrill.