There are too many steps involved in quoting a user's comment.
This update is an attempt to remedy that.
Now, when you double-click a comment, that paragraph will appear in the reply textbox, with the appropriate markup.
You can toggle quick-quotes 'on' or 'off' in your settings page.
As always, feedback is appreciated.
EDIT: Due to some very helpful feedback, I have completely modified the quoting mechanism, switching it from a hover target to a double-click. I'll continue to tweak it, and likely add a mobile-friendly option. Thanks!