And if you have 50+ hours on a project for several weeks, but only 38 on another week, who's taking things too literally? I still don't see it. Look for habitual slackers, look for trends, but don't hit someone who's coming off a sustained period of 'over and above' work effort with the insinuation that they're somehow slacking. Had it happen to me directly once, and seen it happen with other people.
The places I've been without timesheets have generally been less stressful overall, and I think the 'fit things in to a timesheet' model contributed to that stress (for me and for others).
I still don't think you're seeing what I'm saying.
I used to get stressed about time sheets, same as you. Then I had a manager who told me what they were really for. Since then I always put in the stock work week, broken down how ever it is supposed to be broken down. Regardless of what I actually work. I keep my real hours in a personal spread sheet so I know how much time I'm over or under and actually work from that.
As a side note, this extra time you're working is just time thrown in the trash. No one is going to thank you for it and if everyone else is doing the same thing you wont even get any kind of promotion for it since it's not "above and beyond". I know, I used to work 60+ hours for a company. Up until the day they laid me off.
The places I've been without timesheets have generally been less stressful overall, and I think the 'fit things in to a timesheet' model contributed to that stress (for me and for others).