While looking for a T1 crossover adapter, I ran into this: http://www.amazon.com/Cables-Unlimited-TST-LOOP-007-Smartronix-Superlooper/dp/B000G82K86/ref=pd_sim_e_8 If GigE is auto-mdix, when would you use this sort of device? Is it a "belt-and-suspenders" kind of backup plan?