Thanks all for your answers guys,
CMH-17 Volume 1, Chapter 2 does indeed have evidence that CTD is more critical than CTW, particularly for compressive strength with graphite/epoxy composites. Since this strength is partially matrix dependent, this must mean that something happens to the matrix...
I'm writing up the test plan for a carbon fiber composites aileron. The Cert Engineer is asking why I don't do cold temperature wet coupon tests. My only reply right now is that it's not critical compared to cold temperature dry, but I have no concrete evidence for that. Looking back on various...