Talking about hardcore, U must have a lot of free time on your hands to be able to test that all.
For myself I would say that i'm not going to go on such risky endeavours

,IMHO plotting a manual course all around britain, without the use of the UeberBernhard and the manual speed calculation of targets, is already going as far in terms of realism as one would want.
I've seen some recent movement in the 'sextant' mod department which I certainly encourage, but I feel that I am doing the work of 2 crewmembers already.
Furhtermore, I feel that there's a lack of female personnel in the Kriegsmarine on those long trips away from the heimat so,

, enuf is enuf.
p.s. Nyees, let alone other things he wiped off with that rag...

, Eins WO's forehead for example (sackratten) not to mention Frenssen's feet.