The problem with GASO's is quite simple: senior officers feel free to tell you to operate outside them until you ask for something in writing, then they don't have the moral courage to "man up".
It is almost inevitable that if a T* captain does something that causes inconvenience to the system they will be villified. If that same captain bowed to the outside pressure and pressed on and had an accident, he will be condemned for needlessly putting lives at risk.
One thing is for certain, if you have an accident, you or your estate, will be sued by someone should you step out of the protection of the rules because you think you know better. Crown immunity will disappear faster than you can imagine if you have operated outside GASOs and senior officers will amaze you at how quickly they will queue up to condemn you.
It has been pointed out that flying a T* is as easy as flying an airliner - okay cast your eyes at the fatigue issues in the Colgan Air crash at Buffalo. It could easily be argued that the scientifically based CAP371 rules regarding crew duty should be those that the T* operates to. It is not and the easy RAF crew duty rules allow a lot more flexibility than a civil charter operator would be allowed to utilise.
BEagle hit the nail on the head you cannot choose what rules you want just to fit the day. If the rules are wrong get them changed. People with the moral courage to apply the rules when it causes a lot of disruption are what the RAF needs for the its non-operational AT flying. If no one is shooting at you there is no need to to extraordinary measures.