Multiple @-comment notifications; how is it possible?

Question

This comment has multiple (2) @-notifications:

How is this possible, seeing as

• Jeff mentioned this is a no-no;

• Highly-voted requests of this nature have been declined;

• the FAQ on how @replies work explicitly mentions this to be a non-possibility:

  You can explicitly notify one (1) other commenter, editor, or ♦ moderator who closed a question.

The comment was clearly not edited after the fact to insert a second @-reply (although this is also not possible).

---

Here is a more recent comment that has multiple @-notifications:

_{The use of "possible" in this post is used loosely, as it is clearly possible. I just don't know how.}

Answer 1

The FAQ on comment @ replies mentions how this is possible today:

7. Comments containing more than one @name are blocked unless they contain a backtick `. In the latter case, only the first name mentioned using the @name syntax will be notified. For example, @alice @bob Hi!` will notify Alice (if she has participated in that post), but not Bob.

For the comment in question, note that it contains a code-formatted portion (Ctrl + K), which is usually realized by using backticks.

Answer 2

1. Probably only one user got notified.

2. That comment is from mid '10. That question and Jeff's answer is from early '12. It's probable that the check for multiple pings in a comment didn't exist yet. From Jeff's answer:

   Bear in mind this was specifically added because people complained "but I can type as many @usernames as I want in a comment, clearly it should work!"

   So it was added later on. I bet it was added after this particular comment was left.