I find myself in a dilemma, with apps that likely will not work in iterations of the OS above 10.8.5, but now having arrived at a situation where I need to have at least 10.9 for other applications. I know with Snow Leopard and Leopard you could have two–one on an external HD and one on the computer’s internal drive; but I’m not sure if that’s still applicable or even advisable.
Anybody performing this feat, and if so, what do you recommend?
-gf