Yeah Brandon, I have seen this specifically with powder blues. I would almost guarantee that there was an ick cyst in the center of each of those blotches. The blotch itself is obviously quite a bit larger than the cyst. I believe</em> (I have no proof whatsoever) that when the cysts invade the skin tissue, is causes the localized area to "blotch" like this. It is especially prevalent after the cysts have ruptured.
Again this is based on personal observation, and nothing more. When I worked in LFS in NY state, we got in 30-40 PB at a time, all of them with ick. And all of them looked very similar as treatment progressed, usually after the cysts ruptured. It is almost absolutely a stress reaction as you have mentioned, but I almost consider it a physiological stressor to the local tissue, rather than a mental or systemic stress. Again, just my opinion. I would just caution Dwight to be sure that the ick is gone. Without through and effective treatment, this fish will be ripe for the picking from another parasite, in its vulnerable state.