Well its a part of an FOI's job to have an excellent knowledge of the rules, after all the do enforce them, and they dont really fly that much, so they would have lots of time to reflect on the CAO and CARs etc etc
Why dont the FOI's who use pprune identify them selves at FOI's so people then know when they asked a question and an FOI answered it that its likely to be the right answer.
After all like wawa said " in the interests of aviation saftey" it wouldnt be a bad idea to have some type of online question forum for casa where people ask questions.. Why not i say.... Bring it on