Are you sure about that? I havent seen a motronic paper or info about this, but I know on the prev versions (ie lh2.2 /EZxxxk) the ecu would first retard timing (up to 22degress in some cases!), THEN lower boost IF knock was still present. It didn't have fuel enrichment features, altho I can see it easily added to the ecu code.
Or you could just hook up the stock knock sensors to the car stereo... It works GREAT, best $5 ever spent.