Took me a while to understand it as well.
Eugene Allen described it, and I'm paraphrasing because I can in now way write as well as he does, as he "is Metcom" whereas I "am Maximum Effort." He does ironman, rows a gazillion meters a year, and could workout full steam for hours on end. Whereas I can lift really heavy things over and over then come back and do it again shortly therafter. He could use a little of me and I could use a little of him. He's lifting some stones and my "rotunda" is becoming less rotund by running, rowing, and amping up the cardio.
All the best,