I know it sucked for subs, but it was cut short by nuke power and did well enough in torpedoes.
So WI it was workable, or developed more? It does produce serious power underwater, far more than more recent systems. HMS Meroerite could do 120 NM at 25kts which is serious speed and endurance for a submerged non-nuke sub. I'd imagine a more balanced design than OTL designs, with more deisel and battery power, but that makes for a triple propulsion system.
So WI it was workable, or developed more? It does produce serious power underwater, far more than more recent systems. HMS Meroerite could do 120 NM at 25kts which is serious speed and endurance for a submerged non-nuke sub. I'd imagine a more balanced design than OTL designs, with more deisel and battery power, but that makes for a triple propulsion system.