Also, none of methods shown in the video are good for a heatsink like the Xigmetak Dark Knight S1283V with HDT (Heatpipe Direct Touch system). As zipzoomflyhigh said, read what is recommend by the directions in the package.
It really does not make a significant difference. The key is to apply the proper amount of thermal interface material(tim). The job of the tim is to fill in the microscopic pits in the surfaces with a more heat conductive material than air. Not enough tim will not do the job, but the more common error is to apply too much which acts as an insulator.