In fact, Dev response (or lack thereof) is why I don't like 4th Edition. Too many "do it your way" answers to questions, and not enough actual information given to players and GMs who need it.
Everyone who says it's wrong to make a customer base rely on years and years of old information from a variety of sources is right to complain, and AEG was wrong to do it that way, and if/when FFG puts out it's version of the RPG, I sincerely hope they realize this and dedicate enough space to cover what needs to be covered.
I have to agree with this, I remember when I used to follow that forum and it was "easier" to get some answers from the story team than the dev team... It's kinda sad. Maybe it was a decision from their directors, but it was something bad by only saying: "Do it your way". I may understand why though, but it could have been done. I think they thought the "Do it your way" would prevents some dev to tell wrong information, but they could have talked to themselves and come up with the information. As you said, if FFG puts out their version of the RPG, it needs a space to cover those questions, it's something that's call... humm.. customer service?
Now as the "Buff your allies being a breach of etiquette", I tend to disagree, depending on the situation of course. If it's in a duel, yes, a breach of etiquette without a doubt, the fact that you get some help breaks the fact that it's a duel. In a court, since I see the spells as the weapon of the Shugenja and weapons aren't allowed in court, so yes, to me, it is a breach of etiquette, not to mention that the entire Soshi Shugenja are based on this. Otherwise, I don't see why it would be bad to do so.
Why would an Isawa loses honor for buffing up his Shiba Bushi? Why would the Asahina Shugenja loses honor for casting defensive spells on his allies (the whole school is based on this... and arts)? Why would a Kitsu loses honor for casting battle spells on their allies (they are based on battle support magic and the stories also back this up)? Outside of a duel, it's not a breach of etiquette. I would agree if they would be Shugenja in low honor Clans, but they are in the most honorable Clans. If we want to put 2 and 2 together, I don't see why they would be that honorable if it was a breach of etiquette.
The only thing I really wonder is, if a Shugenja casts a spell on someone secretly, a buff spell, does the target is aware that he's affected by an enhancing spell? For example, a Soshi Shugenja cast a reflex buff on a Bushi going into a duel and the Soshi used everything to make sure the spells got cast without any signs of spellcasting. Does the Bushi will know he is buffed? I'm asking this because if the Bushi wants to be as honorable as possible, he would probably say to post-pone the duel since he's under a spells that affect his abilities. That, I'm not sure.