What you're describing is two desktops with a shared piece of hardware between them. If that works for you, great! However it does ignore my original point of "freedom from a fixed position", and why I made it in the first place. If you don't need to move around, then by all means use a Mac Mini. I personally find myself in a lot of places where there are no traditional workspaces, hence I use a laptop.
I addressed why this would work for me in my initial reply. I don't need to work from any point. It is enough for me to work from one or two fixed points. The difference between two desktops and carrying a Mac Mini between two workstations is that the computer itself is the same in both locations so all data is still local. It's all the benefits of a laptop that I actually use. I do not use the screen or keyboard on my MacBook, but I suffer the compromised thermals and bulky form factor anyway.
