The post about groomsmaids and bridesmen -- i.e., women as attendants to grooms in a wedding, and men as attendants to brides -- led to this comment:
All of this is very odd to most people. A sort of mocking of the ceremony, saying, in effect, I'm not one of those common people, I'm cool.
If one is not going to follow [most] general wedding customs, then why go through the elaborate exercise at all?
This, it seems to me, is a good occasion for a few more general words about traditions (and customs, a term I'll use interchangeably with tradition here). I'm not at all against traditions; I see their social significance, I think they generally have presumptive social value, and I think they often have esthetic value as well. The trouble is that appeals to tradition often take too narrow a view of tradition, and as a result often fail to see how even traditionalists must accept that traditions may change.
It seems to me that there is not one traditional custom involved here, but three:
The custom of having female attendants for brides and male attendants for grooms.
The custom of having attendants accompany the person to whom they are personally closest, whom they symbolically "attend" and "stand up for."
The custom of having attendants be one's closest friends (including siblings).
Now the thing is that in my wedding, and -- judging by the comment thread -- many other weddings, it's impossible to adhere to all three customs. My closest friends, setting aside my brother (who was best man), were both women. So I could either have adhered to customs 2 and 3, as I did, and have the women be my groomsmaids. Or I could have adhered to customs 1 and 3, as many people do, and have the women accompany my wife (though they knew me a lot better, and though this would have meant that my wife would have had 5 attendants and I would have had none, excluding her matron of honor and my best man). Or I could have adhered to customs 1 and 2, and substituted some somewhat less close male friends for my close female friends, who would then have been out of the wedding.
With any of the solutions, I would have adhered to "[most] general wedding customs," even if one counted only these three as the denominator. With all, I would have departed from at least one custom. Some custom had to give; it was only a matter of choosing which one.
Now that choice is of course not entirely arbitrary, and reveals something about my (and to a lesser extent my wife's) attitudes. For instance, adhering to customs 1 and 2 or 1 and 3 would have involved a less visible departure from custom, at least from the perspective of people who didn't know me well. But adhering to customs 2 and 3 struck me as a less significant departure from custom, because to me customs that turn on friendship, or on symbolism that represents friendship, are more important to me than customs that turn on people's gender. It's not that all customs that turn on people's gender are unimportant to me, but it's just that they are less important than customs that turn on friendship.
So as reality changes -- here, the reality that many brides and grooms today have many very close friends of the opposite sex, likely much more than before -- some tradition must yield, and it's a matter of which one yields. Over time, if it yields often enough, the tradition stops being the custom and becomes one of many customs.
And more broadly people may depart from one custom simply because they are trying to honor other customs, customs that they see as more important to them. It's certainly not mockery, and neither is it a rejection of wedding customs more generally. It's a necessary choice -- a choice of the sort on which customs themselves are built over time.