I personally am not a fan of IF. I get hypoglycemic too easily, and have actually fainted before when trying it...especially if I am under psychological stress.
That said, I've always been a bit suspect of Poliquin's systems and products. I think IF challenges what he does, and is not something he can make money off.
There's actually some decent information on PubMed regarding ramadan athletes and the relative lack of changes in their performance with IF at this time. I believe there are also two brothers in the NFL who are practice ramadan fasting during the preseason, and it does not appear to have too significant an effect on them..........they still have jobs.
Jason Cholewa, Ph.D., CSCS