Fox tries ‘double box’ to keep viewers tuned in during timeouts
… Fox started testing the double-box format in the spring of 2011, showing picture-in-picture commercials during the final three NASCAR races on its schedule that season.
Afterward, Fox Sports commissioned research from Innerscope that showed that the double-box commercial breaks ranked 18 percent higher on engagement than full-screen ads. Fox found that 84 percent of viewers liked the double-box ad format better than the traditional full-screen ads….
http://www.sportsbusinessdaily.com/Journal/Issues/2013/01/14/Media/Sports-Media.aspx