There are many ways to set up your sheets; and I'm not suggesting that any one way is better than another. I need to change my setup because the lines are wrapping up on each-other due to a swivel on the snap shackle. Far from ideal.
I will mention that if you have a failure of your sheet at it's attachment point it would be better have the two lines independent of one another rather than both as a continuous line. If one of two knots fail you are not at risk of losing both sheets and having a completely uncontrolled headsail. JMHO...