If the original post was simply deleted and re-posted by a different user, the net results would be the same, and would be well within the purview of existing tools. However, all the existing answers and comments, critical and supportive, would also end up being removed entirely. So while disassociating and later reassociating the post in this case may look odd, and may not be what those tools were designed for, their use here seems appropriate.

As for a general "When should these tools be used" guideline?

• Post disassociation should primarily be used when a post owner no longer wants to be associated with their post. This has always been the case, and I see nothing in this situation that changes that.
• Post reassociation is trickier. If there's a good reason and it's done with the full consent of both the original and new post owners, I see no problem with it. "Good reason" is highly subjective though, and would need to be judged on a case-by-case basis.

If the original post was simply deleted and re-posted by a different user, the net results would be the same, and would be well within the purview of existing tools. However, all the existing votes, answers and comments, critical and supportive, would also end up being removed entirely. So while disassociating and later reassociating the post in this case may look odd, and may not be what those tools were designed for, their use here seems appropriate.

As for a general "When should these tools be used" guideline?

• Post disassociation should primarily be used when a post owner no longer wants to be associated with their post. This has always been the case, and I see nothing in this situation that changes that.
• Post reassociation is trickier. If there's a good reason and it's done with the full consent of both the original and new post owners, I see no problem with it. "Good reason" is highly subjective though, and would need to be judged on a case-by-case basis.