Behavior of backticks in editor inconsistent

Repro:

In the comments editor try entering the following text. In some cases it will render it as code/preformatted and in others it just leaves the backticks themselves in, even when saving, and doesn't render them as markdown.

• `code` // ok
• (`code`) // nope
• (`code`) // then move cursor to parens and delete them; doesn't render markdown
• (`code`) // copy and paste this in directly; works ok now
• ( `code` ) // renders ok; now move cursor to padding spaces and delete them; still rendered ok
• code` // then move cursor to before the 'c' and type the opening ` character; doesn't render markdown
• `` // then move cursor between the backticks and type in 'code' (w/o single quotes); renders ok
• (``) // then move cursor between the backticks and type in 'code' (w/o single quotes); renders ok
• enter some text > and hit space. > is converted into a nice little arrow character. Now type ` and then code and then a closing `. As soon as you type the closing ` it will turn the nice arrow back into -> followed by ``code`.

It appears the markdown rendering is based on unspecified user behavior rather than valid markdown syntax itself. Expected behavior is that if valid markdown is entered it will render correctly in all cases.