Is it possible to dismiss every companion to one settlement? This would I assume make the settlement invincible pretty much as they can't die and have good gear. Anyone tried this?

Well sent 2 back and assigned them but they don't seem to want to work... They just stand around

Not sure if anyone cares but after some testing it appears any human companion can be assigned to do things. Robots, mutants, the dog and other non humans can't be assigned to do things BUT they don't seem to count against the total settlement population so they are free and should increase your density in the settlement.

In conclusion if you dismiss every companion to one settlement you will have a larger population and more fun!

Thats what I've been doing, I've only been focusing on sanctuary right now, but my preston bugged and I can't command him to go to any guard towers anymore

Some settlers (like the Abernathys) cannot be told to move. There was a specific message about them when I tried it.

Yeah my companions that aren't human stand in the same spot and talk it is odd. I wish they would pull thier own weight