The real message is this: I do not believe that what you are saying is in the first 164 pages, so it is wrong or invalid or has no place in AA. Rather than arguing the point on the merits, the individual is citing the Book itself as the authority that bars all discussion, which saves the individual the bother of formulating an argument.
Does the Book itself suggest that it is the last word?
Aside from the many references, in one way or another, to the fact we have no monopoly on recovery, the Book itself suggests that more will be revealed.
To attack the 'more that has been revealed' on the basis of the Book that promises that more will be revealed, by God, to those who have taken the actions described in the Book and continue to take those actions, is perverse logic.
It is to say: God has nothing more to say. All has been said. Repeat what has been said, or keep quiet.
It is all the more odd to say this on a discussion board, which, as the description might suggest, is a discussion board, not a repetition board.
This is not to say that the question cannot legitimately be asked: 'is this idea consistent with the principles contained in the Book?' That itself is a principle enshrined in the Book: we are encouraged on page 87 to pray not just those prayers that are in the Book but also any other prayers that stress the principles outlined.
As with most things, balance is probably wise. A free-for-all would undermine the purpose of such a discussion board; a restriction of discourse to quotation would likewise achieve little.
No, the middle way is likely the most productive and the most interesting.