That's a fair point Radgirl about time zones and being different types of work etc and I'm not trying to pick a fight (just genuinely curious) but .. how do you know that it was 'far, far easier than flying within EASA limits'? How can fatigue be measured or assessed or compared across different industries?? Genuine question... and I don't know the answer
Doctors don't always work alone though .. they have nurses to help them, carry out their instructions etc. And just occasionally to call them on bad decisions because they themselves are too tired to make the right one. As happened with this lady I was seeing who once refused to carry out a doctor's instructions to do xyz. He went off on one and reported her to his consultants group who looked into it. and told him "You owe this nurse a serious apology because what you told her to do would probably have killed that patient". She never did get one..
(My respects to you for working those hours by the way!)