you make them the same way as regular textures.
just different file names, should be listed somewhere.
you could apply the same concept to gradients.
full 512 joint textures will end up being another 250k.
basically the same as demon/void force
in the same way that full textures cost around 250k and demon/void gradients cost around the same.
i think done in a subtle manner, they could be terrific.
example:
avwaves scud set
macperfects bikini set @1:28:
or using them as alternate joint colours to highlight sets and complete concepts, like making my torso joints void for continuity, or continuing the line across joints.
finaly makes doing one arm one colour and the other arm another, possible.
quick edit in paint as an example.
but i do agree with you that i can end as a mad clusterfuck of shit
same can be said for some regualar texture sets though, and torso textures