Nope. Nobody has the right to usurp your time. In fact, it is rude of someone to expect that you drop everything to answer every single follow-up question they may possibly have. You are here for your enjoyment, not out of a debt to anyone.
In the specific case you describe I second what J.M. said. In my opinion the most apt course of action is to state that you do not wish to elaborate.
This has several advantages:
OP knows there is no point in waiting for you to reply.
Others will know that you decided actively not to elaborate further and this might very well inform what they do. It is ...
Since no one else has commented yet, the only person you could be replying to is the OP, so the system removes your @-reply (and also will refuse to auto-complete it if you start typing it). See this meta.SO post and the more general info about @-replies.
To signal the (perceived) problem with an edit via a comment on the concerned post was the correct approach. The software allows to comment-notify editors of questions for this reason.
It is also alright that you replied there. Would a longer exchange start it would make sense that you agree to move it to some chat-room or to the meta site or just drop the ...
If your comment is to the author, the @-usernames will often be removed since the author gets notified of all comments anyway. Only if there are others commenting, and there is some chance of confusion, will the system leave them.
Canonical meta.SO thread How do comment @replies work? has everything you wanted to know about comment notifications and much more. Basically, you don't need to include @ in two cases:
you are addressing the owner of the post under which you comment.
you are commenting on your own post, on which only one other user commented so far.
In case 1, if you are ...
You need to remove the spaces to get the notification working if the first part of your username is only one letter, so @dbl or @dblim should work.
See How do comment @replies work? for much more details about the comment notifications.
There are some situations when a user is notified about comments even without being addressed using @username syntax.
Details on how comment-replies work can be found here:
How do comment @replies work?
The situation you linked to in your comment is mentioned there too:
Note if a user comments on their own post and there is only one person who has ...
For the "official" SE specification of @ pings see this MSO answer on how comment replies work. Most likely what is happening in your case is that the software is deleting the recipient since the author is already a default recipient, so the ping is redundant. You can notice this in advance since completion will not work ("Tab" completes usernames here).
If you click the "help" link under the Add Comment button, it explains that the post owner is always notified, making @postowner redundant, particularly in the case where your comment is the first one.
The post author will always be notified of your comment. To also notify a previous commenter, mention their user name: @peter or @PeterSmith will both ...
It depends on the circumstance. If you post one comment or answer (a hint, as you say) and the OP requests further clarification in the comments and you choose not to reply, I believe that is rude. Facilitating mathematical discussion is the reason we have a "commenting" system; if you're uninterested in discussing, don't answer in the first place. If you've ...
If they have all recently been in the chatroom you are in, or participating in the same comment thread, then there is no way to differentiate them. If you ping one, you will ping them all.
user147263 points out that Rule 4 says that in comments, the user chosen is the user
who matches the name supplied
who has participated in the comments on or edited the ...
See Fabian's answer to your previous question for how @-notifications work.
To partially address Bill Dubuque's comment on Jeff's answer, and to make double clear to you that the second @ will not send a notification, Stack implemented a smart system to show you who you can notify and to tell you that you just can't notify more than one person per comment. ...
The answer is yes.
The needle in the 50-question haystack (the intersection of [comments] and [notifications] on meta.stackoverflow) is a link inside one of those questions:
Micro-refinement to notifications for comments of others posts
where this suggestion was marked as implemented on March 8, 2011:
If a user comments on their own post and there is ...
This feature was proposed already more than five years ago Allow for setting comments to "auto-expire", to become "temporary comments" and several times since (see the linked "self-destructing" and "ephemeral" there).
There are some reasonable usecases, mainly in exchanges, like:
@A This is confusing could you clarify?
@B I tried to ...
In chat, the '@' symbol signals type-ahead for names and usually makes an audible ping on the recipient's computer as well as leaving a message in their inbox (the blue inbox icon next to "StackExchange").
In comments, the '@' symbol signals type-ahead for names and leaves a message in the recipient's inbox
As Martin Sleziak comments, your global inbox is ...
To complement robjohn's good answer let me just add that not rarely when it is used in fact it does not do anything as user use it in ways so that it will not result in a notification (or indeed will be redundant as you remarked). Very roughly, it can be used only to reply to users already in a communication not to call somebody into a communication. ...
This doesn't exactly answer the question, still posting my comment to the question as an answer, for future reference:
Anyway, while I can guess to whom I was speaking, sometimes I have no idea.
You might find this tool useful to find to confirm your guess:
Old usernames by almost Living Forever NormalHuman (This tool helped me confirm my guess that his ...
From the Meta Stack Exchange How do comment @replies work? thread:
Matching is performed in reverse chronological order, so if five people named John are participating, @john will match the most recent John.
Note that only users that have somehow participated in a post receive notifications of @replies. From the same answer, the complete list of the ...
I believe that simply choosing not to reply is a bit rude. I would support leaving a comment such as "Please put more effort into this question. I would rather not post a full solution" instead of not replying.
You are the owner of the question, but not the owner of the answers. As such the comments on answers do not automatically appear in your inbox.
Furthermore, your username was not pinged by did, and automatic ping does not work if there are more than one user involved (except the owner, that is). Once Emmad Kareem left a comment it ensured that you won't be ...
There are two purposes for putting "@user" in front of a comment. The first is simply to ping the user. The second is to make it clear that the comment is directed to the user (and not, for example, at the person who wrote the previous comment).
The system seems to assume that all uses of @user are for the first reason and removes the "@user" if the user ...
The main underlying reason for what you see is that in cases were explicit notification is not necessary as it would happen automatically (notifying OP of a post, or OP replying to a unique commenter), it is stripped or at least not supported via autocomplete.
Moreover, only usernames that actually would result in a notification are autocompleted, e.g., ...
You only get notifications for comments on posts that you own or when you participated in the comments and someone addresses you with @Yrogirg. You don't get notifications for comments on answers to your own question, the answers are not owned by you.