What is the purpose of this? I realizes that it flips the drag link upside down but what does that do to benefit me?

 

Flatter drag link equals less bump steer and shift thru flex (as long as trackbar matches angles)

 

As you lift the suspension higher, the trackbar and draglink run at steeper angles. Flipping (moving the axle end of the draglink from the bottom of the knuckle to the top, and then adding a bracket to raise the axle end of the trackbar a similar distance) flattens the steeper angles, bringing them back to pre-lift, while also keeping both bars roughly parallel to each other. Raising the trackbar also has the benefit of helping with the roll-center.

Sort of the same idea as using control arm drop brackets for lessening the steeper angles after a lift (which also corrects the caster).