I'd say Brag's right: we are getting too experienced and too good

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The RL kaleuns did not had a chance to complete as many patrols as we do. For example, Otto Kretschmer sunk 266000 tons in 16 patrols, which is about 16000 per patrol. When I started to play, this tonnage would be quite a success. Now, after completing God knows how many careers, I'm not satisfied if I come home with less than 75000.
BTW, the most successful patrol was the one of the Gunther Hessler, when he sunk 86000 tons, commanding Type IXB U-107 in spring '41.