The idea is to set the TV with no artificial sharpness, however, there has been many anecdotal reports that some model TV's actually set the 0 sharpness level at the midpoint of the adjustment (like 50 of a 100 point scale) and introduce artificial softness below the midpoint, based on using calibration discs, etc. Whether that is true or whether some TV's just happen to be ridiculously soft without added sharpening, I have no idea. I have seen this effect myself as with one set, with a calibration tool, setting at 0 made the line borders completely blurry and I didn't really start to see halo artifacting until I was at about 75-80. Best thing to do is just set it to what looks best to you and not worry too much about it. A calibration disc of some sort will be of some help.