Typically alternative keyboard layouts are installed as a mapping at the operating system level, I don't think the author is proposing a keyboard with that hard

Typically alternative keyboard layouts are installed as a mapping at the operating system level, I don't think the author is proposing a keyboard with that hardware layout. And most modern OS's allow for switching key maps on the fly with little effort. I worked in a lab with a guy who typed exclusively in Dvorak and there was no issue with pair programming along side him nor for him to get his key map on shared workstations.