Imagine practicing a scale on the guitar. You could just repeat the scale over and over, but you could also add rhythmic variation, or play two notes up and one note down. Based on the article, it doesn't seem like moving the goalposts (ie, fret spacing) is the critical point, it's just that you don't want to just blindly do the same thing over and over and hope to get better.
Well, my violin teacher used to say that there were three important stages that a musician has to go through - playing badly and being unaware of what is going on, playing well and being unaware of what is going on, and finally, playing well and being aware of what is going on. When you've reached that final stage, you don't just repeatedly play a tune and hope to get better - you play it, hear your mistakes or what you want to change, and then repeat those sections and adjust them until you are content. Blindly repeating patterns is something you should get past relatively soon if you're hoping to get anywhere with an instrument.
That sounds a lot like the 4 stages of competence[1].
Unconscious Incompetence: You don't know that you don't know. (I don't know how to drive a manual)
Conscious Incompetence: You know that you don't know, and start learning the skill. (I'm learning how to drive a manual)
Conscious Competence: Your skills have improved and you understand them, but there's a lot of manual work involved. (To drive a manual, you do step X, Y, and Z)
Unconscious Competence: The skill has been internalized and is automatic. (I know how to drive a manual without thinking about it)
