It would be really nice to have more extensive work on how to mitigate these kinds of dynamics as I'm certain we will see more and more of these projects and I'd like them to be healthy for a change.
Humanity: Evolve! ;-)
http://meatballwiki.org/wiki/VestedContributor
VestedContributors think the rules can be bent for them because they've been around so long and done so much good work.
As for keeping volunteers equal to avoid the problem, that need not mean keeping everyone identical. Leadership roles can rotate, with finite term limits. That way every leader today knows they will be the underling tomorrow. (This also keeps everyone interested and motivated as nobody is every stuck on one task/job).
But is that inherently a bad thing? The way you state it, I'm getting that you're implying that it's bad 100% of the time. If you're looking at it in terms of black and white, I guess just hearing "rules can be bent" is bad, but I don't think it's that simple.
I think there are times where the rules can be bent which creates an outcome that is beneficial to all. Times where the rules don't account for certain variables/situations and those incidents need to be handled differently (or with care). I think it's a complex problem and it may need a complex solution.
The best, and I mean absolute best volunteer teams I've been a part of have always had a leader at the top with absolute authority. However, he or she never abused their power, and rarely flexed their absolute authority, preferring to take up the mantle of "benevolent dictator". In those cases, some amazing things happened. We got our work done ahead of time, group moral was sky-high, and the projects were a massive success. Things "just worked".
Point being that it's much easier for them to maintain high quality with low effort.
You showed this well. Thank you for finding this pattern and telling about it clearly.
> The answer is to keep all volunteers equal.
(Un)Fortunately this would break. Logically, how can you have one group of equals enforce their rules with unequal power? Naturally, influence (roles(?)) emerge(s). For social animals to want to stick together over the long haul, (1) an elder's view needs to carry a good bit of weight. This makes it possible to retain experience and membership, because these elders are our gateway to the past and they get tired and battle worn. The young learn from those with the experience and use it to build their future. (2) Members need to both use influence and limit it. Mocking leaders and their work, behind their backs and in-front of them, joking with them over the flaws in their work help them to keep their heads from filling with hot air. When someone takes on more responsibility, people will naturally and comfortably give them uneven support if they mutually respect and believe in eachother. This means some have more influence than others. When this flowing power gets a kink in it and builds up in any one place, then it will flood the basin. As long as work gets done and individuals cultivate good relationships, then a community will stick together and most everyone will feel like the community has good balance.
My experience with this: studied this a bit within anthropology and sociology, lived with these dynamics in and among Drupal (a self-described do-ocracy, perhaps a holocracy) community members for over ~10 years, and have a deep interest in natural processes that contribute to social order.
A related snippet from you guessed it with several links to springboard into related research:
Anthropologists maintain that hunter/gatherers don't have permanent leaders; instead, the person taking the initiative at any one time depends on the task being performed.[13][14][15] In addition to social and economic equality in hunter-gatherer societies, there is often, though not always, sexual parity as well.[13] Hunter-gatherers are often grouped together based on kinship and band (or tribe) membership.[16] Postmarital residence among hunter-gatherers tends to be matrilocal, at least initially.[17]
https://en.wikipedia.org/wiki/Hunter-gatherer#Social_and_eco...
If you are walking in the woods, everyone has down/slow days. Hiking/climbing groups know this and so rarely have dedicated leaders. Look at the military groups that occasionally climb mountains (ie wounded warriors on everest). On day one they throw the entire "rank" thing out the window. They know it doesn't work for mountaineering. Instead decisions are generally made by the person least tired/hungry/dehydrated at the time. That's how a hunting party would work: If Bob's got a sore foot today, he isn't going to be the one flushing the deer and instead might be today's planner/leader.
I've seen this with charities, open source projects, and it was a constant problem when I worked in film/tv (interns). Things always go south when you have volunteers bossing around other volunteers. Newcomers show up eager but depart quickly, normally after some dressing down by a more senior volunteer. Without pay in dispute, they rarely make complaint. They just stop showing up. And who can blame them?
The answer is to keep all volunteers equal. That's probably impossible for a project like wikipedia, but they could certainly do more to ensure new volunteers are not so bullied by the old guard.