BOAC
I have read your post and fully undertand it. However I disagree with it.
Obviously if you choose not to go into discretion then the easiest way is to cite fatigue/not fit etc etc.
However my point is I can refuse to go into discretion for whatever reason and there is sweet FA they can do about it.
It happened recently on an Airbus. The captain was rostered to max scheme and went over before first push.He informed the company he would not be operating sector 3 about 5 hours before he was due to. The service was cancelled. He was invited for a chat which came to nothing and BA have been informed by BALPA in no uncertain terms as to what will happen if anyone gets penalised for this sort of action.
The erosion of our status (particularly in BA) is evident.
We do generally keep the show on the road unlike our work-shy collegues down the back, but occasionally we remind the company just who is in charge.
NN