I just saw Lendl play this setup on TV. It seems like you could do this with 2 pieces of string, but the middle strings (the black ones) would probably use a length of string well over the normal half-set of 20 feet. Has anyone tried it and measured what is needed? I envision doing the inside 10 mains, ending at the top, then start your white crosses up top before you go back to the black string to do the crosses starting with the 4th cross.with the white string you could run the top 3 crosses, followed by the left outside mains, then botoom crosses and finally the right side mains.
It is so weird that it makes me want to try it, though it probably sucks and shouldn't be tried more than once. Also, it makes me feel some degree of pain for my racquet to go through such a process. Probably low tension would be a good idea for a first run.