What the author says the main point of the device is not accomplished by the device – trying to keep laser wandering and tracking effort as minimal as possible. This idea, like so much of the tripe sold for CD’s, is a holdover from vinyl days that doesn’t ‘cut it.’ On a vinyl disc, if the hole was off-center compared to the imprinted spiral groove, the turntable arm would wander in and out while the needle rode in the groove. Shaving the outside edge in such a case would mean that the outside edge would no longer wander compared to the center hole, but it would not in any way change the relationship of the spiral groove to the center hole. If a CD has its digital ‘tracks’ physically out of line with the center hole shaving the outside edge will not change this. The only benefit, if the off-center hole means that the CD is out of balance when spinning quickly, would be to assist in improving balance and reducing physical vibration. This one thing may be a benefit in some cases, but of course you realize that any off-center, off-balance or out-of-round physical imperfection was present when the CD was 'burned' so shaving the outside edge does not correct for imperfectly burned data. The reading laser and interpreting electronics in your player had better be able to handle mild imperfections regardless of how much edge shaving is done.