When I played in the beta, all color crystals that I encountered (except yellow ones) said something like: "Not useable by Dark/Light Side Level 1 and above".. can't recall correctly, but you get the point I guess being neutral would then allow you to use all color crystals? I don't know Neutral Jedi/Sith... I'm not a fan of Revan, so I only skimmed through his wookiepedia site - but didn't he like reach a point where he was neither Jedi nor Sith? Suppose that's a neutral as it gets