What that guy is calling a Mach drill does not really look like that when viewed, for example, on the CF GPP video. I don’t think the marches-not shown on the video but shown in Mach’s book (thanks, number 2!)feature the stepping over action and the a-skips definitely do not in the GPP video.
The guy who did this youtube video is much more in line with Seagrave, and other’s version of the drills despite his tagging the name Mach to the clip.