The overlay used in Nickles (2003) was perfectly static and originated from the same computer screen used for the 2-dimensional inspection task. Watts (2012) found that an overlay did not improve an inspector’s performance when compared to basic, nonoverlay training, and could be distracting to the inspector if not presented in a way such 6 that the overlay remained in the same orientation and location on the part being inspected. The discrepancy of results between Watts (2012) and Nickles (2003) was likely due to the overlay setup used by Watts (2012).