I’m not a fan of altering mechanics to emphasize any certain component at the cost of another, or forcing an erect posture earlier than is natural to the athlete. It sounds like his ground contact times are too long for this portion of the race (like you said too long pushing). A cue I use is to focus on “striking” rather than pushing the ground. By being forceful and striking through the ground, he can continue to have good stride length while meeting the ground “stiffer” and improving his turnover via shortened gcts, as long as he is powerful enough (weightroom/plyos) and mobile/flexible enough to handle the new rate. I trust your expertise, but you did ask for input. And trust me, despite being new to the board I’m qualified in my own right, didn’t mean to offend you, just alot of times what looks slow to the eye mechanically can be quite fast.