it's quite normal to come across newbies making very short posts especially in technical board and mining boards. For some I've noticed they are basically bitcoiners offline they just come here to find solutions when they have issues.
It's normal for people to create an account looking for a solution. It's not normal to create an account to
post "an answer", especially when there are many doing it within an hour.
Well, you only assumed I believe, no one is completely sure if those accounts actually belong to the same person or not.
And if the account actually belong to the same person, then what he or she is doing isn't right for sure, but then, there is nothing much we can do aside report the accounts for monitoring like Mia said.
I believe the mods will be in the best position to monitor and take appropriate action on any of those accounts when such is absolutely necessary; to keep the forum clean and maintain her integrity.
So away from the above and speaking on newbies generally now, if is common, very common to find most of 'em making one like posts and comments, but the good thing is that if the account manages to get established, as many of such posts and comments they had made will eventually get deleted by that mod no matter how long it takes.