tex.stackexchange.com is great, active and better IMHO than the LyX specific forum, even though it presumably was TeX only in the beginning.
Question 1) Is there an agreed branch or identifier to post LyX questions (other than the lyx tag) to avoid LaTeX only members getting upset and LyX instruction sets and LyX only content? See @onewhaleid. For using LyX LaTeX code isn't directly useful, and to a LaTeX user anything else is meaningless. A LyX user potentially needs to know everything a LaTeX user needs, but also needs the additional LyX instructions.
Question 2) Is there an agreed syntax for posting LyX command sequences and instructions here?
Question 3) Are there better/more appropriate forums for LyX specific posts? Could the LyX tag be made "Don't complain about LyX content"? When I entered it for this post I read that it indicates this, but how to you post a LyX answer to a non-LyX tagged question without provoking complaint?
LaTeX posts can be very helpful to LyX users attempting slightly advanced/specific tasks beyond LyX, so I am not stirring divorce: Just a new forum member avoiding flames :-)