>Please advise me on a logic of a paleo-fast.

As a former faster (a couple times a year for 5-7 days, and some 24 hour
fasts), I was also wondering about fasting and Paleo.  It does seem
logical to me also for at least some 24 hour fasts.  Animals in the wild
certainly do this.  I've always found that giving the digestive track
some time off is very energizing and healing...but that could have been
because I was giving it a break from a lot of carbs...(?)
Certainly when you're sick, it's a good idea not to eat, and save the
digestive energy for healing.  No animal eats when it's not feeling up to
par.
Jacki