Dvorak is much more comfortable to use than qwerty.
The main cost is the fingers needing to re-learn motor memory. Likely with QWERTY your fingers 'knew' where the letters where. When I learned to touch-type Dvorak, my fingers took some time to adjust, and I had a hard time typing on QWERTY.
With a separate column-staggered keyboard like the Corne, I imagine it's easier to retain the row-staggered QWERTY on standard keyboards, & touch-typing whatever on the Corne.
The main cost is the fingers needing to re-learn motor memory. Likely with QWERTY your fingers 'knew' where the letters where. When I learned to touch-type Dvorak, my fingers took some time to adjust, and I had a hard time typing on QWERTY.
With a separate column-staggered keyboard like the Corne, I imagine it's easier to retain the row-staggered QWERTY on standard keyboards, & touch-typing whatever on the Corne.