Apologies for not coming in or commenting sooner.....
For starters, is it really that clear that the supervisor is responding to being taken advantage of? I had the unfortunate dilemma of having to urinate after a PCM at the same time a former center manager had the same urge. Eight minutes later, the Steward came up to me to inform me that the center manager had told him that I had to "pee on my time, not the company's." This had nothing to do with fairness or courage, it had everything to do with power & disrespecting a worker. It might also be worth mentioning that this was the first time the center manager had spoken to the steward about my "performance" during his tenure. So perhaps he most certainly did wake up and feel the need to gig me at this opportunity.
Secondly, exactly what is considered "appropriate total duration" of time in the restroom? (Given my knowledge of anatomy and physiology, I have a real difficult time calling it a "privilege") And does this time take into account the individuals circumstances. I get up early in the morning and exercise to keep my body in shape to deal with supervisors like Tie who give competent, industrious employees more work. These workouts require that I drink plenty of water early in the morning. I also have a particular diet which forces me to urinate more frequently. PCMs frequently revolve around health and hydration; you can't have it both ways.
Thirdly, exactly what, when, and why does an employee need a doctor's note for bathroom use? Many factors come into play here, such as age, weather, diet, stress, and fitness. And if an employee came in with a doctor's note for a medical condition that caused frequent restroom usage, like say for an enlarged prostate, does that employee run the risk of being "put on the radar"?
Fourth, if there is a problem in this area with one or a small percentage of workers in the group, what on earth is wrong with addressing only them? I would find a PCM on the subject of basic human functions disrespectful and degrading, not to mention a waste of my time. Sorry, I don't share your opinion that the supervisor is the "heroic victim" trying to make a fair workplace here.