As was just brought up in the discussion about the vote, the current markdown-parsing in the comments is causing quite a few bugs and the associated convenience might not be worth the costs of the bugs. We now have an experimental option in your user-profile to switch to a pure markdown editor, so it might make sense to just remove the automatic markdown parsing from the comment editor and have it just be a pure rich-text editor.
I left two comments that you can vote on to decide between the options.
The issue is not so much dodgy Markdown parsing as such, but the combination of WYSIWYG-ish editing and Markdown parsing. So you type <asterisk>blah<asterisk> and the next time you press space the asterisks go away and "blah" is italicized. This is a slightly strange experience, and makes any bugs there are more annoying, and some people really really hate it.
(The most frustrating experiences I've had with it are actually with the LaTeX integration, which is a lovely thing to have but also occasionally infuriating.)