It was my belief that since every ship in the fleet must move in unison mixing fleets slows every ship down to the match the slowest ship ie: battleships go as slow as carriers or subs.[/quote
With the B/ship, Carrier, Sub combo, you get the benefits of Active Sonar in close proximity to the other two vessels, with a small trade-off in speed. I only use this method when playing as Europe, where the east coast of North America is the primary goal, and you usually get a lot of confusion mid-atlantic (especially with fleets coming up from Africa and South America as well).
Also, you get a maleable flotilla of 12 self-contained units which is protected as well from the rear, as from the front. It would be interesting though, to put this up against a very well managed 'battering ram' of B/ships, followed by Carriers (spewing fighters then bombers), with Sub packs lurking always in the background.














