I think we need to keep a few things top of mind in this discussion.
1. The OP has a D800e. He knows what it can do. He also has a P65+. He knows what that can do. He wants to put the P65+ on a tech cam, let's help him.
2. The D800e is a truly amazing DSLR, but it doesn't have the lenses that a lot of us need. Of course, not all architectural photographers use lens movements. I know one very good one who has a tech cam and prefers to shoot with a Phase DF. He sees the tech cam as too cumbersome.
3. The Canon 17 TSE and 24 TSE are amazing lenses and give many photographers and clients everything they need. That is not true for all photographers and all clients. Whether the image is shot to be mostly done in camera or mostly assembled in post has a lot to do with this. Personally, if I could put Canon TSE lenses on a D800e, and have it tether seamlessly in C1, I don't know that MFD would interest me.
4. If you put a tech cam and a 5DII on the same tripod and shoot the same image/image series, there will be a difference (particularly in the look, color and dynamic range of artificially lit wood), but whether that difference is meaningful is another story. I see the difference and it is important to me. Unfortunately, my clients do not for the way they use the images, which thus far have been almost entirely websites. I have never printed a comparison so I can't say whether that translates into print or not. Generally a client picks an image and only that one gets worked up.
5. Stitching works really well on an internet forum. On a shoot, particularly when there is exposure and focus bracketing, it can be more difficult.
6. Some people have shooting styles that dictate a certain type of gear. I hadn't thought about this, but an assistant on a recent shoot pointed out that a lot of how I shoot, particularly when I'm in a hurry could not be done solo with a tech cam.
7. There are a lot of people with heavy MFD system investments that prefer to use a DSLR. There are others shooting with a single lens on a Cambo DS with an Aptus 22 because that is the only way they could afford a tech cam. Neither is more right than the other.
Now, back to your previously scheduled $hit fight.