When soloing a couple of turns last night for the first time, I tried the all out German naval assault on the British navy. I sent the Home Fleet and 2 submarines against Scapa Flow (sea zone 9) and sent 2 submarines against the Canadian navy (sea zone 2).
Sea Zone 9: I lost 2 ships to mines and then the British and German fleets destroyed each other, leaving a lone British transport.
Sea Zone 2: Wilfrid Laurier’s Royal Canadian Navy Cruiser sunk both of my submarines before slipping beneath the waves, brought down by a slow moving torpedo. Once again, a lone transport calmly rode the waves.
So, my all out German assault on the British navy resulted in the wholesale destruction of the German navy. Thus, the British didn’t have to spend any money on warships, only more transports to bring troops to the front faster.
On the plus side for the Germans, a couple of amphibious assaults on Belgium by the French and British resulted in high casualties as the German shore batteries obliterated whole divisions. Artillery rolling at 3 or less at troops coming ashore helps make up for CP naval weakness (or, in my case, naval non-existence).