What is the proper way of action about this new user, who spammed 14 identical answers in around an hour?
The answer is rather poor in my opinion, they boil down to:
This is complicated, I suffered from it, please see my solution in code [link] and my upcoming tutorial [sitelink]
Sometimes the answer is not even ontopic:
Here's rather disproportional users response. My comment was edited to add "and promoting your site":
Now he is deleting his answers I had pointed as off-topic and one with comments quoted above.