Fox enlisted actor Rob Lowe, and comedy, at its upfront presentation today to underscore broadcasters’ message that advertisers should stick with tried-and-true TV shows and forget about emerging online competitors.

In a recorded routine, Lowe earnestly said that “online viewability standards” are “so important to me.” He noted that TV ads fill the entire screen while online ads sometimes just fill “half the picture for a fraction of the time.” His bit warned advertisers not to “buy crappy online video where you don’t know what you’re getting.”

Fox hopes to reinforce that impression by co-promoting its broadcast and cable networks and the “incredible scale that sets us apart,” as Ad Sales President Toby Byrne put it. The combination of “our star power” with “our trusted environment” drive three times as much brand familiarity and sales as “sub-prime video.”

“People don’t just watch our shows,” Byrne says. “They have deep relationships with them.”

He described VOD — where ad skipping is disabled — as “DVR replacement viewing” that’s “good for all of us. And your brand should be there.”

And, picking up the theme that NBC also introduced this morning, Byrne says Fox will offer data that “demonstrate the value of a Fox partnership” That includes information from recently acquired TrueX Media, a firm that offers online viewers opportunities to determine how and when they see ads.