OMG...tell me thiis guy is wrong about micro four thirds

People just get hung up on the idea of the same framing (same field of view, same photograph).

You change between different format camera bodies in order to change the framing of subjects (while keeping Focal Length, F-Number, and Camera to Subject Distance constant) ???

But that would be roughly the same framing (would it not?), thus changing the DOF ...

I calculate that the difference in the background blur-disk diameter (relative to the image-frame dimensions) is proportional to the ratio of the physical dimensions of the image-sensors used.