I have undergone severe training and adaptation of Dvorak(Simplified two handed layout) and discovered the single hand typing alternative Dvorak Left/Right handed layout. Since I have two (currently still healthy) hands, I did not even think of glancing the construction of the "disabled" layout.
During researching on keyboard layouts, I discovered some funny new inventions such as Frogpad, Half qwerty, Single handed maltron and Fitaly layout. It stimulates my desire to look for typing one handed which allow me to free the other hand for multitasking or simply let one hand idle for mouse pointing.
With two weeks of Dvorak lefty training, I managed to type primevally such as googling keywords and typing short message and email. I don't know if I am the only person who found the single handed layout useful to daily purpose?