@eltranquil: Thanks for the Yamaha document, it is VERY interesting, though I am convinced that they don't tell the truth:
"Audio CDs burned using conventional methods display considerably higher jitter values (audible playback errors) than pressed CDs. "
I recently compared the jitter which was measured by Plextools/PX-716A on several commercial cds and their copies, created WITHOUT GigaRec, and the copies were all burnt on a different recorder (not the Plextor). The Jitter of the original CDs was in all cases higher, approximately about twice as high as those of the copies.
I already expected this result because for me it is hard to believe that a cd produced by a mechanical process (stamp) would be as exact as a individually burned cd.
Nevertheless, the document confirms that the absolute level of jitter would decrease when using GigaRec in the "wrong" direction (I actually already knew about this option, thanks anyway )