I'm slightly hesitant to get involved in this discussion because I don't fly in Irish airspace, but it has lots of parallels with the UK where I fly. The key parallel is what CAP 774 calls "agreements". I've never really worked out how these are different from what existed before March this year, but I've always assumed that this term "agreements" applies to controller statements such as "report if you wish to climb above 2000 feet" when you've just told them you're leaving controlled airspace. These are strange requests because (in the case I'm particularly considering) you've just left a CTR on a "not above 2000" clearance and the base of CAS above is 3500; IFR traffic is never going to be lower than 4000. It seems to me it's a very fine line between courtesy and legal sanction if you don't comply with that request. Yet another case of pilots having to guess what's going through controllers' minds - and I don't mean any criticism of controllers there. It's just that I've always taken the view that there's much more scope for being explicit i.e. saying why you're doing something (if time allows).
NS