I never played football. I was what you might call "skinny" or "unathletic" most of my life. Perhaps still?
From an implementation standpoint, the article makes perfect sense. I can imagine telling a group of 16 year old kids "See that heavy shit over there? (Pointing to keg, log, axle, or stone) Let's see who can shoulder it/put it overhead first" works better than discussing the intricacies of oly.
But.. in terms of training effectiveness, I'm not sure I ever get close to reproducing the speed or power when in shouldering a stone, sandbag, keg, or racking a log as I do with a clean or power clean. At near max weights, I attempt a slow, incomplete triple ext, and then begins the death march as I roll said object up my torso.
Maybe squats aren't appropriate for football because I'm not able to ask the big fellow across from he if he could kindly sit squarely on my shoulders so I can squat him properly? hah.
No doubt, SM movements could round out a solid S&C program, teach guys to apply force in less than ideal situations. But to replace o-lifting?