Every Imm knows how the area they write works, and what it contains. For what it's worth, Balrahd was an Imm, he wrote an area and I'd wager he knows stuff about that area that nobody else knows, as well as the line Imms walk when they play morts, so I give his opinion on the topic a bit more credit than yours.
All the rest of the players are left to figure it out. If they want to. Most go to a new area, look for new gear, and if a quest triggers great, but otherwise they don't do in depth exploration, at least until they have more down time or the area is a little older (and so less crawling with people coming to pk you) There is usually a general trickle of information that comes out from new areas.

One of the ways some of the more complex aspects of an area actually do get out to mortals is through the writing immortals playing a mortal and disseminating the knowledge that way.

The simple fact is while he knew how to do or obtain something (because he created it), the ability to do it was not unique to Nepenthe or his characters.
There is a big difference between knowing the steps to do something and being the only one who can ever complete those steps.
Nepenthe and silent operated more on the former. Any character could do what he did, so long as they figured out how to. And many regular old players did just that. Sure, they burned through a hell of a lot of con and characters to do it, but they did, and that's more what Nepenthe wanted to give players in those areas, high risk high reward. If he wanted to cheat, he could just give his characters physical resist, resist magic and a whole host of other shit that nobody would ever know existed to create an uneven playing field. The fact is he really didn't need to cheat to win, he was just a better player than everyone else, and he put far more effort into one character than most of us put into ten. Nobody would argue he also didn't benefit from having a vast game and area knowledge to work with. (I always hated hell and silent because of the very OP nature of what they contain- but it was really more cause I never bothered to learn them myself)

Knowledge is not cheating. How a person comes by that knowledge can be debated as to if it is cheating, but there is no real way to insulate an area author from knowing what an area contains.
So I fail to see what you are bitching about as cheating.

Now, editing a pfile, having an Imm give him something just because- sure that's cheating. He won RCs, have you read those roles, they're quite good and should win. He was basically the type of player that Imms normally reward, just by virtue of his approach to playing the game.
Exploiting knowledge he gained by virtue of contributing an area to the game is not cheating. Being better than you because he knows more than you about CF is also not cheating.

And given when you started playing, and that Daevryn was mostly gone by then anyway, what the hell do you even care about what Nep did years ago or how he played?
How did him abusing a Ysigarth vine, or playing Cabdru or whatever, all of which was before I ever played a character in anyway impact you? If Gromm was your firsts, that was years after Daev played any real character of significance.