Muscle Tension Pattern

Hi Coach,
few days ago I listened to a podcast from BarbellShrugged with one of the strength coaches, where he described an appropriate muscle tension pattern of posterior chain. What I mean is that there is a test where an athlete lies on his chest and raises one leg. The trainer puts his thumb on right buttock and the small finger on the right harmstring. Then he puts the other hand on his left part of lower back. Then he tells the athlete to raise his right leg. The trainer checks if the pattern is ok by feel. What he should feel is firstly glutes are activated then harmstring and at the end the left part of lower back.
Here emerges my question: if someone fires harmstrings or lover back first, how to correct this pattern?