I worked in a call centre a long time ago. At the end of each row of desks was an elevated desk where the team managers sat, precisely to enable them to watch each person on their team.
It says a lot about folks desperation for a job to deal with a boss with that mindset. Sure, I'm fine with observation posts if I'm in danger and might need help pronto. By all means, have an observation desk if I'm feeding crocodiles, but not to monitor my daily work.
I thought have a cubicle in an office area built inside the old fuel bunker for a power plant 50 feet underground where radio and cell didn't work and you heard a wind noise beyond the wall to clear the air of potential fumes sucked. I guess I was wrong.
I feel the same way about this as McDonalds managers directly observing the kitchen and cashiers: nothing at all.