I was finding the game pretty easy even though i play with 100% realsim and use alot of mods to simulate historical accuracy. I wondered how this could be then it dawned on me. I have access to one thing a real skipper does not, a reload button.
I started playing with no savegame files, in other words once I load my savegame, I delete the savegame file. This considerably changes the dynamic of the game. Every decision has a real consequence, if you make a mistake there's no going back.
I currently do this for patrols but I'm not brave enough to delete the entire campaign savegame... yet. I doubt anyone would make it passed 1941 without reloading at least once.
The only hickup with sh5 is that damn immersion killing autosave feature. I have to continually delete savegame files as they are created. thanks ubi