"Extra" knot in the line?

Been seeing more of this lately. Why are some people putting figure 8 knots in their rope between the tie in and the friction hitch?

Is it there to help keep you straight on which line is which?

Troy

This knot has only one purpose: to aid the rescuer in the event of an aerial rescue. It both id's the bridge rope so only it will be cut and helps prevent the rescuer's knife/saw from also cutting the supporting ropes nearby.

You will be amazed at how easy it is to cut a rope with someones body weight on it. We all should be practiced in aerial rescue just like CPR. If I need either the knowledge will not help but if you are rescuing me I hope that you know all task well.

See you at the top,
Dan