Re: OSP for 4
What if the really interesting thing would be not only to have an OSP for 4 astronauts but TWO of them, docked to the station?
THat way, 8 astronauts can work at all time in the station and in the case of an emergency involving only one astronaut, only one OSP would return back, leaving the ISS still manned by 4 astronauts.
Raoul