Duty times for engineers? Yes, but....
I think the whole duty hours thing should be looked at again - I see nothing wrong in having a relatively high flying rate during the day - after all, if you're on standby or away from home you may as well work, as you get more tired when you're sitting around.
What I would do is rigidly enforce days off. Half the benefit of a day off is knowing you're going to get one, and when they get screwed around, your mental concentration goes, and at that point you may as well go home anyway. A day not flying is not a day off!
Phil