jennab:
Why would you want to add text that's secret but the reader doesn't know it's secret?
I like to do it to see if people will even bother sharing information.
For instance, I'll throw in a "<Player> noticed that Blah, Blah, Blah..." just to see if that person will mention that they noticed something.
When you include things in Private to, they're bright orange and everyone knows 'HEY, THIS INFORMATION WAS ONLY GIVEN TO ME!' so they jump to share things, instead of it being an organic decision.