I'm not old enough to answer the chicken vs. egg on which came first: 2 crewmen or systems requiring 2 crewmen, but we (HS) needed 2 for SAR, PR, and yes running both the ASO (acoustic) and TSO (tactical) systems. My best guess is 2 crewmen was taken for granted when the 60F was designed, because plane guard.Small point of order... HS guys can correct me here, but I believe they had a 4th crewman for ASW. With a more modern SYSCONFIG than the Bravo, I always wondered how much of that was truly workload and how much of it was because of the smaller buoy magazine the Fox had.
Similarly, I think 1 crewman was assumed for Romeo development, because that's the way HSL had been already been doing it with the 60B. I've also heard people say the aircrew (including pilots) were never expected to run the whole system alone. The datalink was intended to let the ship help with sensors. Ha!