I ran into a similar problem this weekend on a friend's car. It has some of the worst swirls I've ever seen, and I finally got a chance to see what I could do with just a PC on really horrible swirls.
I started working on the hood and was able to restore some of the gloss and remove some of the swirls. However, there's a cloudiness in parts of the hood that I don't know what to do with. When I polish it, a lot of the cloudiness goes away (not completely), but then returns after about 15 minutes or so. It's definitely not oxidation, because it doesn't feel or look like it's on the surface... it actually looks like it's in the color layer (this has a clear coat, it's a '94 Infiniti G20, dark green), but if that was true, why would polishing have any effect on it at all? Thoughts?
BTW, I tried a variety of polish and pad combinations, just to see if anything worked differently... 1Z UP, SFX1, DACP, PI-III MG, AIO, and others... The more aggressive polishes obviously did more for the swirls, but nothing seemed to affect the cloudiness any differently.
Also, I won't be able to try again until next time I see the vehicle, so I won't be able to test out any theories right away. I was more interested in just hearing if anyone's run into a situation like this, or what people think it might be.
Thanks!