this is the first I have heard about a “fatigue expert” Drew Dawson... Where did he come from and what does the academic base his fatigue model on?
LL, Professor Drew Dawson has dedicated his entire academic life to the study of sleep and more fittingly to this thread, fatigue and the measurement/management of. The Centre for Sleep Research has been consulted by most transport industries in Australia and from some abroad as a world leader in this field.
You may read more about him and his teams work here...
http://www.unisa.edu.au/sleep/
Perhaps if you find yourself in ADL one day, you may wish to drop into the university and speak with them about their work. Have a good day.