It says that it's restricted to DS, and it is if you don't put the <FULLNAME> crystal in the same lightsaber, which I'm telling you I've done while being LS. I just checked again, and it works. It doesn't tell you it'll work - it tells you the opposite - but it does. And I didn't cheat to do it either.
ill have to check that out, but my point is they made a ds crystal, why not a ls one as well