LOL.. 2 captains.. It ain't that hard! You just have to have divers that can enter the water on command and immediately descend vertically in an expeditious manner. Normally not that big of a deal for the boat driver or divers.
There's some skill involved. I nearly missed the Hydro on a dive last summer in a stiff current. It's a pretty good sized boat, 350' long, heading north to south (stern to bow) in the gulf stream. We we given a 400' lead, dropped at about 100' a minute, and still barely caught the stern. If he had given us a shorter lead we would have never made it on the wreck.