This is a test using the Collapse-Pro-Matic / Collapse-O-Matic plugin in the comments area.
1. Does the shortcode work in the comments? Probably not by default. Let’s see.
[expand title="Read More"]This is the expanded text of the comment. I have a good feeling this will not be allowed by default.[/expand]
Nope.
2. Does the shortcode work when the following is added to the functions.php file?
add_filter( 'comment_text', 'do_shortcode' );
Yes is does.