It might also be great for SMA to do something similar- it might actually give a decent reason to join- but it's hard to say how useful it'd actually be, since they don't actually have any real weight over our AEA contracts.
That's debateable -- since the SMA is directly responsible for there being Stage Management seats on Council. Before my time, but as I understand, the SMA served as sort of an outside caucus to effect those changes. Looking at current council makeup, I see that the Third Vice President (function: National Stage Manager) and at least 4 other members are also active SMA members (including the SMA current chair).
(Is there a council member online here who can speak to this?)
More recently, I would note that many of the active members of the Off Broadway committee are also SMA members and I believe that the SMA forum sponsored last year is directly responsible for both language and negotiating tactics used in the last set of negotiations.
If you are interested in having more input into the AEA contracts, I suggest joining an Equity committee (whether SMA appeals to you or not) if you haven't already. (It's free!)
The wheels of negotiation turn slowly (and never forget that AEA contracts are negotiated with producers) but they do turn.
Committees also have significant say in how concessions are granted to producers.