> However, em-dashes do make the reading voice in my head change over to an old-timey radio announcer so that is cool. That is cool. When I read a parenthetic

> However, em-dashes do make the reading voice in my head change over to an old-timey radio announcer so that is cool. That is cool. When I read a parenthetical in parentheses it's like someone is talking to me while I'm trying to watch a movie: Even if the information is useful, it's annoyingly distracting. The same parenthetical in em-dash form doesn't have this same effect on me. However—and I hope you'll bear with me here—for the most part the information in a parenthetical is either not needed or important enough to justify its own complete sentence.