Sorry to be so late with this reply.

I'd say that I have very nearly fully recovered from the dermatitis. I still have some spots of slightly pink skin, some of which are not quite as smooth as the surrounding skin where I did not have dermatitis. The fasting only really helped in an obvious way while I was fasting. Once I started eating again, the dermatitis would come back. I don't fast regularly. Most often I fast when I take long international flights. I have one scheduled for tomorrow, in fact, and I plan to fast.

I don't think the recovery is chaotic in any real sense. If it were, slight changes in diet or other conditions would result in greatly different outcomes. I do suspect that fasting may help to reset the body, by prompting the body to degrade and dispose of older proteins and use up stored fat.