>>57210886David hates coffee. Not for the reasons you think.
When he works night shifts, he used to drink coffee to recover, but drinking too much coffee made him inmune to caffeine. This was so bad even energy drinks no longer work. If he is tired, he is most likely to start headbanging.
He is trying to find other things, like natural teas or more healthy beverages. But no luck.
So everytime he "feels" is going to start, he moves around and washes his face. So far progress is slow, but at least positive.