Most stuff concerning Submarines, regardless of country of origin, is classified. This includes - weird as it may sound - even old technology, considered obsolete (why? Because if you know how the old thing worked you can make a pretty good guess how the successor/new thingy works).
With that in mind, think about the "hard" sources like Jane's and the likes. They, as well as everybody else make (educated) guesses on the capabilities of military technology. But while it seems that they produce facts ... well they don't (in some if not most cases). If they would actually do that, especially on (lets say that together class) CLASSIFIED technology, the guys with black suits and shiny badges would be with them in no time at all.
It is similar but sometimes not as stringent with every "branch" of military technology ... some things are a bit more in the open (considering that you can get manuals for an F-16 online) and some are not.
Bottom line ... the information for the mods is gleaned from open sources and made up with SWAGs (Scientific Wild Ass Guesses). So citing other mods as sources for the alleged correct settings is like saying that aunt June's apple pie recipe is the standard and only correct way and aunt Sandy's apple pie recipe is wrong.
In the end everybody has to pick the apple pie he likes
