Nudges. Why?

[arguskos]

Why is the following part of the forum rules?

Nudges
If a Mod finds a thread going off-topic, they'll post a friendly message trying to nudge it back on-topic – how hard a nudge depends on how far off the rails the thread has gone.

Such a rule quashes discussion and the mutating nature of internet discussion. I understand destructive derails, or derails when a more appropriate thread exists, but in many cases I don't understand why the above is needed.

Additionally, the moderation staff has said, on multiple occasions, that they don't recognize thread ownership. If that's the case, then off-topic discussions that are still of merit (such as here (http://www.giantitp.com/forums/showthread.php?t=180806) ) seem completely fine, since the thread still serves a unique and interesting use.

What was the reasoning about the "Nudge" rule?

[olelia]

I believe it is there BECAUSE of mutating internet discussions. This forum is for complete randomness, unless your in silly message boards. The purpose is to have a coherent subject of each thread and then to at least follow along those tracks. If the conversation is veering from the original topic it should be put into a different thread.

[Andraste]

While a person can't control a discussion, the topic should. Discussion should stay around whatever the first post is about. This could lead it away from the OP's intentions, but still be about the topic. It shouldn't be about some random thing that people start talking about that has nothing or very little to do with the original topic.

[arguskos]

While a person can't control a discussion, the topic should. Discussion should stay around whatever the first post is about. This could lead it away from the OP's intentions, but still be about the topic. It shouldn't be about some random thing that people start talking about that has nothing or very little to do with the original topic.
That's understandable. However, when the topic is still being discussed, but in a very different way than the OP wanted, I don't see the issue. I've seen this fairly frequently, but the only good link I've got atm is the one in the OP.

[Roland St. Jude]

Sheriff of Moddingham: Two reasons. First, most thread nudges are to keep a thread from veering any further into inappropriate territory, that is to say, Forum Rules violating inappropriate topics or hostilities. It's a way to head off discussion trending toward rules violations before actual Warnings or Infractions (or additional Warnings and Infractions) need to be given. It's an attempt to steer people away from getting themselves in unwitting or impulsive trouble.

Second, some thread nudges are to prevent a thread about X to get overtaken by tangent Y. This requires judgment about whether: (1) X and Y are closely related, (2) X and Y can be discussed concurrently; (3) new discussion about Y is choking out discussion about X, (4) Y would be better discussed in a separate thread, and so on. It doesn't stymie any discussion, it just redirects it into separate threads where a moderator thinks it would be helpful. And you're right many times it isn't needed, threads shift slowly to incorporate additional ideas and topics, but sometimes it is needed. The rule exists to put people on notice that non-punitive nudges about what should be posted where may occur.