Pushing later with the left leg helps with late acceleration of the arm. It's actually beneficial for late acceleration to utilize the most power from everywhere late. Another helpful thing is to bend both knees equally more so that it take more time to straighten the left knee. It may delay the lifting of the leg to beyond rip alone. going too far down in the stance will again begin stressing the joints. You don't want less than 120 degree angle at the knee for health reasons.
Flat shots need running on the center line of the tee and planting each step on the center line. Anhyzer needs running from rear right to front left with the plant step hitting the ground to the left of the line you're running on. Hyzer is the mirror of that.