Need ability to prevent hidden text created with HTMLComment macro from showing up in a search

I'm trying to convert our RoboHelp 7 docs into the wiki. RoboHelp has a feature called conditional text. You can tag a topic (page) or any text with a conditional tag, then use the conditional build tags in the output (online help or PDF) for different audiences (and hide certain text for certain audiences). For example, we might have one topic, and we use conditional tags in different parts of the topic for the administrator or end user. We're reusing topics instead of copying them, and there's less of a chance for error because we're only editing that one topic.

The problem with the HTMLComment macro and with the Excerpt macro's "hidden" parameters is that even anonymous users will be able to see the hidden text in a search. We need a way to comment out text so that it does not show up in a search. It would be nice for those with permissions to still be able to search for hidden text, however.