It was recently brought up with me that it could be potentially terrible if someone on hubski were to post good content, let it get shared so more people see it, then have the poster change the link into something, well, much less popular. I understand the reasoning behind letting people change the link, but I think that if it were a popular site, this kind of feature could be taken advantage of by trolls and advertisers.
This is it. If a user wants to discredit themselves, I am ok with that. Of course, they might have a short term advantage from it, or be disruptive for a short time, but IMO it will sort itself out to their detriment. Removing the ability to edit the url after time blocks this bad behavior, but trust is a powerful thing. I'd ignore someone that did this.
This, and technical issues, is why reddit hasn't added this ability in the 7 years it's been around. Even with comments it's happens occasionally, which can be frustrating. I don't see why someone would really need to change the link anyways. If it's a different link it's worth making a new post. That being said, the title is something that I think is worth being able to change.
But you can edit self posts and always have been. CuntSmellersINC used to post heartwarming stories, watch them get upvoted to the front page, and then change them to tales of pedophilia. I myself have said things that are flattering to the hive-mind, then once they've been upvoted to the stratosphere change them to things that are condemning of the hive mind just to get a controversial trophy.
I had to update a comment earlier today and thought the exact same, not that it was popular or had any comments. This feature could also be used to discredit another user. For example, Person 1 posted a critical argument about the tea party movement. Person 2 responds Yeah I totally agree. Their actions have proven that they are only interested in protecting their financial interests. There will never be peace and true equality while they continue to influence American politics. Person 1 then changes their original comment to I hate [insert persecuted race]. An extreme example, which I am sure would never happen. I guess any further comments could easily be removed or edited by their authors to reflect the change. A feature could be added to identify when a comment has been added once it has already been commented on.