Well, having just plowed through seven pages of this thread I feel I must add my 2 cents, too.
IMC, I have given all my players 4 additional skill points. I gave them a free feat. I nixed cross-classing restrictions, and they may buy feats they're not eligible to (but can't use it until they are). That doesn't mean I change all monsters the PCs meet to adhere to the same rules.
Likewise, I might use opponents with abilities taken from books the players don't have access to (like, for example, a creature from Monte Cook's Legacy of Dragons using an Arcana Unearthed spell).
Plus, I would really much rather play Storyteller than D&D.
ETA: I am also a staff reviewer for the German dnd-gate, and I have had two instances where I deliberately looked for adherence to the game rules, one was a book of NPCs, and the other a monster book (both with about 50% of its worth, or more, in rules materials), and EVEN THEN I did not check the skill points of the write-ups except for a few randow checks to see whether they were "generally correct".
All this I just wrote to illustrate that I am in no way a rules-lawyer. In fact, I have a "whatever works"-policy.
BUT I get annoyed when the rules of the game are nixed for no reason whatsoever, in a product I payed for. You cannot possible explain every case of not adhering to the rules in a manner that I understand where you are coming from, because you have a word count limit and must use this limit to put as much adventure into the book as possible. So I don't know why your imp has bluff.
Now, likely, this example is silly, because 90% of all GMs would probably not even notice that this imp has bluff and the standard version doesn't, let alone complain about it. Despite what you say, even this thread doesn't have that many people complaining about changing the imp to have bluff in a reasonable manner, but only some people who think this should be done within the context of the rules.
Now, why don't have imps bluff skills? Or as you put it, "shouldn't they have the ability to lie?". The thing is, an imp can lie all day if it wants to, it just isn't very good at bluffing. It might think it is smarter than it thinks, or it might use more cunning methods of betrayal, like telling half-truths (as long as you regard bluffing as lying, which is an issue that can be, and has been, argued about). I won't retread the myriad of methods open to anyone in achieving the effect you desired that are not only within the rules, but really quite painless.
In fact, I haven't read my core rulebooks faithfully since the advent of 3e, I have just playing the game, and I knew all about these rules.
But that still isn't why I am posting. I am posting because I sincerely hope that you are Jeanry Chandler. Why? Because your signature link to his "manual" has given me the impression that you are. Why is that important?
Really, your stance towards the game you want to write game materials for professionally, and your reaction to your consumer base (even if it is a small minority) has put me back. You start off by belittling the game you are trying to write for, posting an example that does not illustrate your point very well (no matter ho often you claim it does), but rather throws a doubt at your knowledge of the basic rules you are aiming to support with your product. Then, you jump to conclusion regarding the intentions and gaming styles preferred by posters, showing more than a little predisposition to put negative labels on anyone disagreeing with or critizising you. You continue with posting exaggerations, cynical remarks and either severe misunderstaninds caused by the predisposition I already remarked on, or blatant lies concerning the general response and nature of this thread. And after you have stated that you dislike the game you write for, after you have hand-waived even minuscule changes to your design that would lie perfectly in the rules on the basism of some assumed behaviour that has not been proven right in any way in my experience, and after you have belittled or name-called many of your potential customers while keeping a somewhat aloof tone, in short after you have acted childish in a thread started by yourself in reaction to posts requested by yourself, you still expect me you buy this product, should it ever see the light of day?
I am sorry, but I must echo James Heard here. You are not going to get my money, or more precisely, Jeanry Chandler is not going to get my money, and I am glad you stopped that project. I am sorry, and I am sure your home campaign is great fun, but there are a lot of writers out there that need my money as bad as you do, and who don't profess their dislike for their own choice of game system that publicly as well as don't act as immature as you did here. I really don't care whether your imp has bluff, changes into a girl (which I find to be a far, far bigger change to the standard imp), or whether Kind Arthur can only draw the sword out of the stone after drinking a mug of virgin's blood. It's your way of dealing with people trying to help you (in a civil manner, mostly) that has caused this.
Sorry, this was overlong and rantish, but that really riled me up.
P.S.: And if you want to have any chance of succeeding as an author, imo you should read this post, think about it, and then disregard whatever it is I wrote you think doesn't apply to you.