I'm not sure what the camber is with the Whiteline LCA since I also have GC camber plates and currently sitting at -3 for camber. I believe the difference might be from the cast-iron and aluminum hubs for fitment. Since a friend friend with a MK6 GTI tried to fit the Whiteline ball joints on his car and they are rubbing with his BBK setup. If anyone is interested...I do have a set of Whiteline ball joints for sale for cheap, however they do have scratches on them from the rotors rubbing up against them.
Interesting, something about the layout of the aluminum knuckle must provide additional clearance vis-à-vis pushing rotor further away from the ball joint than on the cast-iron knuckles. For reference Whiteline states .25 degrees on negative camber and 3 degrees of caster on their LCA's while SuperPro claims .5 degrees of additional camber and only one degree of caster. Either way, hearing of this on the Mk6 really makes me think this isn't a problem that's solved with whatever alignment spec you wind up on.
A proper shame since I was really looking forward to running these, but ah well. And hey, if anyone else wants another pair of cheap slightly ground down Whiteline ball joints just let me know