Bump * UPDATE *
After a useful discussion in the uboat.net forums (not conclusive though), I am:
a) Updating the mod with new, more conservative values. See first post.
b) Creating a "mirror" / alter ego mod (of the DG Removal) which models the additional drag caused by an upgrade to the conning tower, or ultimately the U-Flak configuration. Since I consider the U-Flak the queen of the U-boats, I will call the mod U-Flak Queen Drag

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Have Fun!
VonHelsching