They lull you to sleep by running and running and running, then catch you off guard with a pass. They play keepaway, using up time, but if they fall behind, they're forced to play lefthanded; i. e. throw the ball.
Most of the time in these flexbone offenses, the passes are called out before hand. Some guys use RPO but not many and not very much. The pass is hardly ever an option with these runs. Too much to do.