This question is quite related to this one: How to best handle the "Possible vandalism of own posts" flag?, but I would not like to narrow it to the case discussed in that question. More importantly, this question is about what should we, mere non-diamond mortals, do about the automatic possible vandalism flag.
When is it OK to delete several posts and when it is not fine? Will ♦ moderators undelete the posts if they're good? How good have them to be so it's worth undeleting them? What would that assessment be based on (votes, subjective evaluation of the answer's quality, etc.)?
In short, I'm trying to understand when should we flag those actions and when should we just ignore them (or, perhaps, marking them as an invalid flag).