House and Yes Man are pretty much mutually exclusive though. Yes Man is about as useful as a lawn ornament as long as House is alive. And if Yes Man is in charge, House is effectively a corpse.
If there were four Couriers and each helps a faction, it's impossible to say who would win. Yes Man and House cannot both be in power, and there is also only one Securitron army. And any action taken by one of the couriers would be cancelled out by one of the other couriers.
One of them would probably die fighting the other in the Mccarran monorail fiasco. One helping bomb it, the other trying to stop it. They’d also clash in a lot of the side faction quests, so I’d say legion and NCR might be mutually exclusive as well. Legion courier also has a chance to kill yes man/house courier when they try to activate the securitron bunker, while they were sent to blow it up.
