I can be a U-boat captain
I excel at Silent Hunter IV (and III but that was many years ago). I know how to ID and track targets, plot firing solutions, to attack convoys, to manage damage crews. I know how to use sonar. I've even manned the deck gun and AA by myself. I've played it on 100% realism (limited fuel, dud torpedoes, etc), and even have installed advanced realism mods such as the Trigger Maru overhaul from Subsim.com. I've gotten out of pretty hairy situations with many destroyers circling above, and have racked up a fairly decent tonnage during my various careers.
I watch Das Boot unimpressed. Sure it has good acting, but how hard can it really be? Back then they had to go to school to learn to be a captain, unfortunately for them there were no simulations to learn on. I really don't see anything too difficult that I've not already learned from the comfort of home.