Lots of things are part of my story that are not relevant to carrying the message of AA to alcoholics. The question is: what is my purpose in sharing about other addictions?
The Big Book had it right. Keep the focus on the alcohol. Mention drugs. But do not get distracted. I mention Al-Anon matters in AA occasionally, but I do not keep it the focus even of any one share (except when we're on the chapters To Wives or The Family Afterward in the Big Book).
There is nothing to stop people going to more than one fellowship; in fact, many people do.
Many sponsees of mine also go to OA or Al-Anon. No one really wants to bring either of those topic areas into AA, and both of those fellowships stick very closely to their primary purposes too.
Whichever fellowship you are in for that hour, stick to its subject area. If you particularly want to talk about a particular substance or using pattern more appropriate to another fellowship, go to that fellowship that day. If you are having a particular obsession with crystal meth, and you go to an AA meeting that day rather than CMA, CA, or NA, why did you make that decision? That is the real question.
At a broader level, if you consistently want to talk about your using and you did not drunk so much, why did you pick AA as your primary fellowship? Why not pick a fellowship more obviously suited to your problem?
Sometimes the argument is made that the recovery is better in AA. Well, fine; that may be true in some areas. However, many OAs visit AA for that reason but then take what they have learned and start up strong OA meetings. I have sponsored OAs in this way, who have set up the first strong, Big Book-focused meetings in their respective home areas. But they don't share in AA meetings except in relation to their alcoholism.
There is no natural entitlement to public confession in AA on all matters that come to mind. AA has a specific purpose, to recover from and help others recover from alcohol. Treating the room as an alternative to therapy with the room acting as the therapist while you say whatever is on your mind is not what AA is about.
Since my last drink, I have never treated AA as a place that I can hijack for my own purposes (e.g. to gain the questionable therapeutic benefit of talking about problems publicly); I treat it as a place where I am invited to fulfil a particular role: to share about how I have used the twelve-step programme to recover from alcoholism.
There is nothing to stop someone in AA who wants to talk about their using from asking one of the millions of members of AA if they could sit down for a coffee and talk. At such talks, anything goes. You may talk all day, all week about anything. Complete freedom!
The question, therefore, is not whether one 'may' talk about drugs in passing (which one obviously may, in the spirit of the Big Book—although some hardliners disagree). The question is really where the sense of entitlement to talk primarily, consistently, or continually, or at length about drugs—as opposed to alcohol, drinking, alcoholism, or recovery from alcoholism using the Twelve Steps—is coming from. That is about putting one's own needs or desires first, ahead of group and fellowship welfare. Recovery is supposed to be about putting the group and the fellowship first, with personal recovery taking a close but second place. The question is not what is best for you but what is best for the group and the fellowship as a whole.
The drugs-in-AA issue is therefore a Tradition One issue, not a Tradition Five issue, which is why the discussion gets side-tracked and lost down a dead-end.
The most compelling reason why drug talk—or Al-Anon talk, or OA talk—should not become the focus in AA:
In parts of the country where most people in recovery are basically druggy, but the meetings are mostly AA, there is nowhere for alcoholics to go to get identification. I've been to meetings in New York where no one mentions alcohol. Fine, talk about drugs, but if that takes over, a new fellowship would need to be founded for alcoholics to talk about alcohol. It could be called Alcoholics Anonymous.