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- Don't remove the @ part of my comment 11 answers
This is by design.
"It's not a bug, it's a feature."
What it is is a lack of interactive feedback.
Now that there's this "shortcut", the comments text box no longer hovers the user's name as an option for auto-fill and tab-completion.
This is jarring for the users who were already accustomed to using @ every time, not just in ambiguous cases.
For example, replying to a user Bob who doesn't believe how it is would be as follows:
TabYes, that's right. This is essentially what happens in the general case.
What happens now is as follows:
The cursor is no longer in the comment field. Expecting to be writing text and hitting backspace at any point will change go one page back in the browser. Nothing will be entered and only terrible things can happen.
Give us a placebo. Give us the same exact functionality with the @ in both the ambiguous and the obvious cases, auto-fill with tab-completion of names, the full shebang. Filter it out however you want once the comment is posted, but let us do the whole song and dance so that things don't break when they don't have to.