> It's a low-speed differential pair that negotiates the initial communication. AFAIK, it's not, the SuperSpeed (USB3) wires have their own independent negotia

> It's a low-speed differential pair that negotiates the initial communication. AFAIK, it's not, the SuperSpeed (USB3) wires have their own independent negotiation; the device switches to the USB2 wires only when USB3 is not detected. This also explains how the proposed VirtualLink alternate mode can have USB3 without the USB2 pair.