They've considered the amount of rocking back and forth torque that might be placed on the drop outs. To reduce that to a minimum (or completely pretty much), to the point where I would have no further concern, they have designed this awesome torque arm that appears to be maybe twice as long as what we're used to seeing, and it attaches directly to the hub via splines. It's a work of art when considering it's purpose. There's very little twisting load placed on the drop outs. The axle is even round for a little extra strength, with no wire running through it! -Al