I tried creating a test mod replacing the textures for one of the Caparisons with unsplit versions of themselves. The result does not look right, it looks washed out compared to Vanilla.
DIFF replaced (looks washed out):
DIFF+DDNA+SPEC replaced (clearly there is also a difference in gloss and specular reflection):
Does anyone know why this happens? Is it due to the fact that the dds files are unsplit, and if so, is there a way to resplit them?