I remember a retrospective article on Friday Night Lights after the show wrapped up. In it, the producers/creators talked about how Kyle Chandler and Connie Britton had such amazing chemistry that they were terrified to let them drive down to Texas together on their own (they wanted to do this to bond before the 1st season started shooting) as they were convinced that by the time the two arrived, they'd be in a torrid affair. Fortunately, nothing like that ever happened and Kyle/Connie were really just BFFs that hit it off immediately.