I must say that I am glad I'm not working operationally at the moment because this FIS thing seems like a real mess. But it also means that I'm not as conversant with and knowledgeable about the new procedures as many others posting here.
Nonetheless, there are some interesting points being raised about the legal and regulatory background which my reading of CAP 774 seems to have overlooked or ignored.
One particular topic, related perhaps to Talkdownman's question, is that CAP 744 describes what happens with controllers and FISOs but there are three levels of ATS provided in the UK, 'Air Traffic Control Service (ATC), Flight
Information Service (FIS) and Air/Ground Communication Service (AGCS)'*.
I know that, technically, AGCS does not provide a FIS but the service is largely indistinguishable from FIS provided by a FISO, particularly for aircraft in the air. What now is the difference between what you get from an aerodrome with a FISO and with an AGCS? Especially with respect to entering or transiting an ATZ?
* See AIC 26/2004.