What worst than often OT? Having metrics to show OT help the project - http://www.jamesshore.com/Blog/An-Energized-Work-Experience.html

Some arguement against work more than 8 hours a day - http://www.infoq.com/news/2008/01/crunch-mode http://jchyip.blogspot.com/2008/01/40-hour-week-is-not-just-about.html