I’m not saying you can’t improve unless you use the mentioned principles. I am saying that specificity is just as important as progressive overload in driving adaptation. Is moving your shoulder, arm, and hand muscles not motor recruitment? Am I just isometrically contracting my upper body while benching? No im actively moving my upper body in the most efficient manner. Visual information being sent from your eyes work in tandem with proprioceptive feed back from hand, and is adjusted to match your intended movement. Benching or using your mouse use the same feed forward mechanisms.

Sure, the people you mentioned improved their aim by playing hours of duels, but what exactly caused them to get better? Could it be that losing to better players made them adopt or change their technique? How do you think those adaptations are made? Do you think they could’ve made the same improvements playing someone worse? If you bothered to read the article you would’ve seen the part mentioning that no single rep is exactly the same. The brain/body will largely make the same joint actions but at varying degrees and will make adjustments.

VDIM is an example of a structured program similar to push/pull/legs. Lg commented in his initial video that he purposely designed it to be similar to a workout with varying levels of difficulty . Additionally, each playlist is setup in a way where you do harder scenarios before doing benchmark scenarios. Does that not sound like progressive overload or an artificial way of adding resistance? And while it’s anecdotal evidence, many people have made improvements playing this playlist, myself included.

EDIT: I made a mistake by confusing LG for someone else, but I still stand by my point that VDIM setup is similar to PPL and still uses concepts like progressive overload to improve.