Unitarians are getting another mention on the BBC News channel, in that they and the Quakers are listed together as wanting the right to conduct same sex weddings. The legislation also gives the local congregation and minister the right not to opt in even if the denomination does - well this is the situation with the Unitarians anyway. There may well be the odd chapel that says no, and more that just do not register. Hull when approached by a lesbian couple agreed in principle to their conducting what was to be their own blessing, but it never went ahead. A few voted against. Since then Hull has had attendance from people attracted in part because of the national publicity that Unitarians are in favour. I'm not sure what happens if the minister says no and the congregation says yes, in that apparently a minister saying no can prevent the premises from being so used. That would count against Unitarian democratic polity: it does not give ministers the right to veto, it simply doesn't force on them what they don't want.
The government's proposals for legislation not only demand denominational and local opting in, but also specifically excludes the Church of England and the Church in Wales from the legislation. The latter I do not understand as the Church in Wales (why it is 'in' and not 'of') is not established. (Update: Nor it seems does its boss - Dr Barry Morgan doesn't want the extra exclusion!) Presumably either of these Churches would pass the laws of their Churches to include same sex marriage and then Parliament would respond - it's not that much different from the Church of England now. But it means that there is no law waiting to be met by either Church. I can't see the Scottish Episcopal Church getting the same excluding treatment from Holyrood, though it and/ or the Church of Scotland just might.
The law could be such that either Church could be excluded until self-included: but, as with women bishops, the Church of England first votes for and then the law gets changed nationally. Presumably the Church in Wales decides what to do for itself: so this law of exclusion is almost like the establishment creeping back in.
Nevertheless, the symbolism is obvious: up front a specific named Church is excluded even if it wants to be in (though in practice it won't be). The symbolism is a response to the Church of England lobbying for exclusion and for no difference between civil and religious marriage. The multiple locks plus exclusion mean, surely, that some people are becoming fools for staying in the Church of England.
So a gay lay person in the Church of England, in order to marry their partner, has to pop out to another denomination to get married. It could be that the Metropolitan Community Church is the only 'orthodox' Christian church to offer such marriages (unless the United Reformed Church comes on board with marriage). What of the gay minister, lay or ordained, in the Church of England? Are they going to hop denomination to get married and then return? Would they then get an appointment with their bishop? Surely only those ordained with an old freehold in place will be able to do this without consequences.
If there is going to protest, the most effective will be ministers getting married via other religious means.
Some might marry in a civil setting but surely a blessing for marriage in the C of E would be just as illegal, and it hardly amounts to the same thing as having a wedding that is straightforward religious and done.
The anomaly that would still exist regarding marriage would be that people would be regarded as married in civil society, but the established Church would say some are and some aren't in its eyes (whether civil or religious) or it would just have to be two-faced.
This being two-faced does start to apply to its adherents. You can be two-eyed, but there surely comes a point when you are becoming two-faced. The law is passed on the basis of the absolute refusal of these two episcopal Churches to be involved, and are given solid-in-stone exclusions. At what point in a religiously plural setting does a minister or lay person simply change denomination? No one is forcing anyone to stay in that episcopal institution: what is it about that institution that keeps you there rather than in something more compatible, whether it be the MCC, possibly the URC, or, for clear liberals, the Unitarians or Quakers?