Apparently it has changed.[/quote[
No it hasn't - there have always been limits. All that has changed is that in the past when the Communion has said "this is a limit, please step back from it" that has been enough, restraint has been shown. This time the Communion said "this is a limit, please step back" and they kept going.
But we do share much in common.
Somehow, at some level, we have to have a shared vision of what essentials we must hold in common are. Unless you want to try to define Anglicanism as "whatever overlap there happens to be between the national churches of England, Wales, TEC, Canada, Australia, New Zealand, Nigeria, Uganda, Singapore, Rwanda, Sudan, South Africa,...". But we've never defined ourselves in that way in the past. We've always regarded some things as essential, even while avoiding defining what that is any more than is necessary at any given moment and retaining a provisionality over even that. So we are back to "adiaphora" - what do we have to share in common and what is adiaphora? Each member cannot decide that for themselves unilaterally - that is
inherently a decision the community makes.
'Self-restrain' may have been appropriate when letters were written on parchment and carried by horse and rider - lots of time for self-reflection. We no longer live in such a world.
Self-restraint isn't optional - it's essential to living in a community, let alone a community trying to base itself on the Kingdom of God. We have active programs in schools to try to teach young people self-restraint; why on earth would you think a global community could possibly operate without it?
Perhaps not - but the issue needs to be acknowledged for in the end there will be some form of 'authority' imposed and applied.
It's the authority of any fellowship deciding as a fellowship what the boundaries of that fellowship are. No National Church is obliged to sign the Convenant, but those that do are choosing to form a fellowship of mutual accountability. Which is part of the essence of being People of God, so that should not, in principle, be a problematic thing to do.