Sometimes I would find it handy to have an additional way to emphasize text. We have bold and italics, but it could be convenient if we had a tag (like
<em1>) that would map to a unique alternate text colour that integrates well with the web site theme (for example the colour that corresponds to the
str class for markdown-syntax-highlighted text).
Also for inline code I noted that trying to emphasize a part of it results in inconsistent spacing due to the padding of code blocks (consequence of this question).
Example of use for a vim question where I would see a real use for such a feature:
<em1> is probably not an appropriate tag name, and
<alternatecolor> would be more meaningful.