Obviously, my 4 articles in The Submarine Review are not directly pertinent to the question about bombing of Germany being a war crime. The reader did pick up on my conclusion that the Yamato was sunk by a Mark 13 air to surface torpedo. We know the Yamato was sunk by torpedo. My conclusion about the Mark 13 comes from Naval Odnance documents. Ralph A. Alpher, my father, was employed at JHUAPL beginning 8/1/44 to develop the magnetic influence-contact exploder (Mark 10). These records show when it was deployed--many months before the sinking of the Yamoto. It is reasonable to conclude that TBMs would have been using this air-to-surface torpedo by the time the Yamato was sunk. This is about as conclusive as you'll get. The documents I found were not in the National Archives.
As for loss of submarines, I can't comment. The "happy time" for German U-Boat aces was over by the end of 1942. They used hydrophones to detect ships in convoy--which isn't relevant to degaussing. However, once the Allies deployed Magnetic Airborne Detection to find U-Boats under the water, it was the end of the U-Boat war.
Security was always a paramount issue. So, although the Proximity Fuze was deployed on D-Day, it was not used until the Ardennesoffensiv (Battle of the Bulge). Risk of the Germans finding an unexploded bomb and retro-engineering it was significant. The war was over before they could produce their own proximity fuze, although the concept originated in the 30s.
Interestingly, the Proximity Fuze was declassified in 1976 and by 1980 Ralph Baldwin, one of the Ph.D.s employed to work on it, wrote a full account. He also published, privately, a book in 1999 called "They Never Knew What Hit Them" which describes German infantry accounts of dealing with the Proximity Fuze during the Ardennesoffensive (Battle of the Bulge). The learned never to leave overhead shelter. The basics of the Proximity Fuze were declassified and even published by 1946. Several accounts of "scientific" progress during the war at the Office of Scientific Research and Development (headed by Vannevar Bush) were published shortly after the war. However, details such as employed in my articles were obtained through an extensive search of the National Archives, and fortunate searches of what I could find through the internet. Some documents I have from 1950-55, during which my father worked at JHUALP, have been reclassified. This applies to anything having to do with underwater ordnance, which would include the Mark 13 torpedo. I was lucky.