In a discussion on the possibility of limiting anonymous edits to the Wikipedia -- resulting from the mad dash of unwelcome activity during April Fool's day -- a participant replied "This one comes up again and again, and the consensus has always been 'nope, anon edits will continue thanks.'" I am always cautious before making such a declaration of consensus because of what I call the "lost minority." When a particular policy of the community is likely to drive away some participants one must be careful. I explain this by way of a group within a room of which some folks have bad gas. Those with the gastronomical distress, of course, don't complain. There are some, who aren't bothered by the smell, or think that the smell is a worthwhile trade-off for the presence of the farters. And those with sensitive noses simply can't take it. When the latter group propose that something be done about this issue, such as limiting the amount of broccoli that is served at lunch, or developing a nose filter, people discuss the issue, and perhaps it gets added to an agenda. In time, the group is polled, and surprisingly the consensus is to do nothing. But, what is happened is that a significant portion of those with the sensitive noses have already left.
I don't know if this is the case in this Wikipedia example, but this concern is relevant to issues that are likely to drive participants away. And in time, that lost minority might become an alienated majority.
Sj on 2005-04-05
I should clarify, since it was one of my mailing-list posts that triggered that subthread, that I was being sarcastic in my post. The inclusion of anonymous edits is, for good reason, a cornerstone of Wikipedia's community, philosophy, and success. And the greatest vandalism threats come from people who could easily employ bots that create accounts and log in, so optimizing what happens to anons would be false economy.
A cleverer way to improve the handling of edits from anonymous or unknown users, which has itself come up many times (but waits on implementation) : automate and structure the distributed process of reviewing such edits, so there was no repetition of work, and no edits passed by unremarked.