I have been unsuccessful in finding the details of the HSTC as it applies to the AT. I think it will be a full function traction control that is rider programmable. In the Dec/Jan issue of Motorcyclist magazine they rode the new Honda 213xxx super bike that has HSTC. The article went into some detail explaining that it was the Bosch IMU- inertial measurement unit that measures acceleration in all axis's. It feeds this data to the ECU which is also sampling wheel speeds and engine parameters to only allow enough torque to the rear wheel so that rear wheel spin up/drift will be limited or controlled to some defined limit. I am waiting and searching for confirmation or better info.