Yes...Admiral Charles Lockwood(COMSUBPAC in WW2) was the movie's technical advisor-can't get any better than that. Actions depicted in the movie were based on the USS Growler, USS Cavalla & USS Albacore at the Battle of the Philippine Sea, and that of USS Darter & USS Dace at Leyte Gulf.
Yes. Those were things this movie really had going for it in my opinion. Though my favorite line was by Martin Milner. "Gee, that's the first time I saw a sub get knocked off."