Concerning learning from past events to get to a better future, two major points are being missed:
Collective accounts, even when set up in good faith and in a completely up-front fashion, are against the SE Terms and Conditions, which clearly state (term 1, 2nd paragraph, 1st sentence) that a subscriber to SE must be an individual.
Moderators don't have the authority to waive this provision in the ToS. While they're not required to have perfect knowledge of the ToS or to take responsibility for enforcing them, let alone interpreting them, it is surely good practice for them to notify admin when such an account is created so that admin can decide whether the provision in the ToS should be disregarded.
Very important, massive great edit
I think maybe by staying strictly with the facts here I may have failed to make my point clear. The fact that a collective account is against the SE rules, and the simplicity of that fact, and the fact that this hasn't even been mentioned on PSE until I just mentioned it, shows just how appallingly badly the mods handled the whole business with the collective @MinderDaemon account.
Nobody disputes that that account was set up in a completely above-board and honest way, by four named existing users.
The moderators should have known that a subscriber has to be an individual. That's not a difficult fact that you need to be a highly experienced lawyer to understand. It's just as straightforward as the requirement that all users be at least 13 years old. It's all right to say that user individuality is not a matter directly affecting site content (neither is user age), but let's be serious here and recognise that moderators should have a basic knowledge of the rules and the terms under which people subscribe to SE sites. Yes, even if legally they're not agents of SE Incorporated. Let's note too that moderator @Emrakul is happy to talk about other aspects of those rules and terms at considerable length, here on Meta, in his effort to set the confines of the community discussion about mod policy on the promotion of other sites which has arisen after his and @Doorknob's decision to ban @Randalthor for a year.
The moderators assure us that the decision was given great consideration before they finally signed off on it, and that they sought advice from an SE official, who backed them. Look, OK, they probably didn't know the rule. Or they did but they thought it wasn't material. There aren't really any other possibilities. But if the whole business had been properly reviewed at that stage (which obviously it should have been), why didn't they realise that the reasonable course of action when the rule-breaking @MinderDaemon account was created would have been for them - or perhaps more appropriately for admin, having been informed by them - to write to the account, maybe copying in each of the four individual accounts, saying "Sorry guys, collective accounts aren't allowed on SE"?
Then none of this would have happened.
Whichever way you look at it, the matter of the setting up of an account in clear breach of the rules should have been considered prior to what was done with that account. And if by error that didn't happen at first, then it should have happened during the long and serious consideration and certainly when the matter went to the official.
Lest there be any disagreement here, let's recall that no-one has been accused of using their individual account to carry out excessive and suspension-deserving promotion of the other site. It's what was done with the collective account - which should never have been set up, but which everyone agrees was set up in good faith - that was the stated reason for the suspension.
Whose fault is it that the route wasn't taken of simply notifying the guys that they'd unwittingly broken the rules? Well mainly it's the moderators' fault. Partly it's probably also the fault of whoever in admin is responsible for ensuring that moderators know how to do their jobs properly and for ensuring that the terms and conditions aren't obviously breached. But this appears to me to be such a massive dun goof, compounded by the letter the moderators sent notifying @Randalthor of his suspension (which he has published), and compounded by their wriggling about saying they can't reveal details because it would compromise his privacy (when he's publicly given them permission to reveal details), and by @Emrakul's attempts to set the limits of the debate about the decision he himself was part of (there's a massive conflict of interest there), that I'm going to say what a lot of people are saying privately:
the moderators have acted incompetently, and they still don't get how they have acted incompetently.
So if you agree with the statement that
the decision to suspend @Randalthor for a year was wrong
please upvote this answer.
And if you do not agree with that statement, please downvote this answer.
I am not au fait with SE site graduation practices and moderator elections, but it was said recently in the chat room that the amount of traffic that is generally speaking considered sufficient, if sustained, to justify graduation, is usually reached by PSE when @Randalthor is here and, when he's not, it's kind of almost but not quite reached.
I have no doubt that those who are so inclined could engage in all sorts of "edge case" discussions about that. I'm certainly not going to. But it seems to me that it does suggest that now is a pretty good time for there to be moderator elections. That can be an important air-clearing ingredient in how this community moves forward.
Moderators here aren't elected at the moment, but there needs to be a community response to their decision, and so long as this post doesn't get removed, or made unvotable on, there will now be such a response (even if it's silence!). I am quite sure that once the moderators have taken on board what that response is, they will realise the importance of considering their position.
"How do we move past the absence of our top contributor" is the wrong question because it begs the question that needs to be aired: was the suspension right? Nobody is calling for "mob rule". It is legitimate for that question to be considered in a grown-up way by the community here on meta. The decision is capable of reversal.
I am quite surprised that nobody has asked that question here already, but this is the right place to raise it, because at the end of the day all decisions by moderators are supposed to be about helping the community function well. Every member of a community has the right to have an influence on how a community functions. The recent decision has certainly affected us a lot. Has it helped this community function well or hasn't it?
I have tried to phrase the key question here as simply as possible: was the decision right or wrong? Have your say.
Since the usual definition of "sockpuppet" involves an intent to deceive, this is the wrong word, as is "spamming", in relation to what has actually been done. (Both are appropriate, of course, in the larger context, but I am talking about their specific use in relation to the relevant known actions.) They obscure the matter of the SE rules and the question of whether the mods completely dun goofed. I do not want to insult anyone, but I'm sorry but I'm going to have to be negative here. Two of the moderators have seemed motivated by a kind of petty-official desire to control stuff and to argue like the most barrack-roomy of cod lawyers (or is it nightclub bouncers: we don't make the 365-day rule?) for their decision, and @Emrakul seems hell-bent on trying to dominate how the decision that he himself co-made is viewed by the community (plagiarism is a complete red herring). That's a far cry from acting as the "human exception handlers" that @JonEricson envisages as the proper role for ideal mods. And even @JonEricson is missing something important when he talks about human exception handlers and then talks about the exceptional circumstance of the suspension of the top user. Yes, that suspension is exceptional - but it's not a circumstance that the moderators are faced with and are handling; it's a circumstance they decided to cause! Something did come up, yes - the creation and use of the collective account - but when it did, it seems that the mods showed no awareness of the SE rules and spectacularly went off on one.
The pre-existing and existing policy is that some promotion of other sites is allowed - albeit, and understandably, only in small amounts - but what @Randalthor did was so small that really you have got to stand on your head and get into ridiculous contortions to say that it could have been any smaller without vanishing, and once you've realised that, you have to conclude that it doesn't deserve being kicked out for a year for. (It can also be pointed out that all four users are co-responsible for that account, so why single out the guy who clicked the button?) Remarkably, @JonEricson's answer above actually promotes the aforementioned site more than any of its owners have ever done in any question, answer or comment on the SE website! He says it's a good site, worth your attention, which is promotion in the literal sense. Something is clearly amiss.