If you really wanted to optimize something involving living consciousness beings like a machine, at least you should consider things like the need to take a piss as a hard constraint and design the system around it.

Don't get me wrong I love factorio like the next guy and understand the idea behind your thinking, but there should be limits to that thinking in the real world. And if that doesn't convince you consider the efficiency loss of a depressed worker with a urinary tract infection.

Honestly - and I don't mean that as an insult - I hope for you to experience (just once) the loss of dignity that not being able to visit the restroom on your own decision will give you. Might make you realize the hell this kind of thinking leads to.