Ken, to start with, you have to be ambidexterous ... Really, there was a TV show commemmorating the 70th (?) anniversary of the end of WWII. One of the people interviewed was a B-17 flight engineer. He was asked if he remembered the pre-flight switch setup of the engine and electric panels. After being assisted into a B-17, he went thru the checklist with no errors. When asked how he did it, his reply was basically that he had repeated it so often that out of necessity he HAD to know it. Same thing with astronauts -- there is no room for 'OOPS!'.