I don't have one of these, but here's my guess: It's all about when you press down on the bar.
The route behind the block is so the block isn't stopped by the back of the cavity when you dive super low.
The extra route beneath the sprints is so the springs don't scrape against the bottom of the cavity when you dive low, as they are going to get closer as the block goes back and up toward the top of the guitar.