You do have a point. There are other things beside a sensor, and Canon is certainly no slouch in FPS, AF, processing, video, and a lot of other qualities. And lenses! In fact, they are better in most of those areas, that is why they are competing. The fact still remains that their sensor is s##t and will only cause their cameras to produce not to their potential.
Imagine a D800-like sensor on the 5Diii body! *drools*
Yep... and i imagine crappy ISO performance, I imagine the extra work and WB issues that is popping up with the D800 just to get the image in the same realm of the 5d3 in terms of overall color, pop and effect, and imagine all the extra HD's and card needed to support the files.... Uhhh no thanks... I can see where some styles and some forms of photography would benefit, but it is not the all to be all... Canon is to old slide film as nikon is the negative film... The slides just had better pop, better and vibrant colors, more "wow" factor... Negatives COULD have more latitude but in the end, a lot more work/care was needed to get negatives in print to get remotely close to the slide image. The same is being proven true with D800 files and the 5d3 files...
That is just sour grapes talking. The "pop" you talk about with 5Diii is its lack of DR. High DR images have flatter look and you can post-process (the horror!) to make it fit your levels. D800 has better detail, better DR, and better color, all critical to a technical image quality.
Lets face it, 5Diii's sensor is no better than 5Dii's. 5Diii has improved on AF and processing, though. But the heart of the image is its sensor, which is sorely lacking.
May be Canon needs to stop listening to "everything is fine" crowd and innovate, perhaps?