There is a diffrence betwen real life and a sim (no matter how realistic it is). If I was a real life kaleun on my first patrol I dont know if I would even engage a large convoy while beeing it was beeing protected with escorts- probably I would just be stalking some lone ships the first few patrols. The fact that any mistake will cost you your life and lives of other 70 sailors that depend on your judgement makes a man think not twice but three times before he attacks.
In SHIII I sank 80t in my first patrol (hit the same convoy 4 times and dodged DCs 3 times each time for over 2h of game time- In RL if I was going to raid a convoy and after that get nastly DCed I would just turn away home... Not go in for more revenge
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