If someone needs to be taught how to do this stuff, they should actually be taught how to do it and not simply given a "hint". There's so many ways that we can demonstrate how to use comment replies, but without users actually learning the ins and outs of the systemins and outs of the system, observation alone will always be sufficient to learning how to use it.
This is the same kind of problem as the fact that we see a lot of "@Downvoters" and "@OP",
the people who may use @Yi to respond to Yi JiangYi Jiang, people who try to reply to multiple users, as well as proper @ syntax that is directed at someone who hasn't even participated in the discussion at all. And, far less frequently, people who don't realize your name is not spelled the way they think it is.
So if you see a new user reply to you without the syntax, feel free to give them a link to the rules. It'll be far better than assuming they'll catch on.