The blue line is a little too high for Turned Shoulder Plane angle.
Usually it's drawn up through the armpit at address. (10-6-B)
The Standard (flat) backstroke shoulder turn component is meant to take it back to that line and then down it.
He's not far under it.
You have it on the Squared shoulder turn, a much steeper plane. (10-6-C)
Too much knees action, weight rolled to outside of left foot.
"Plant the left heel." Harvey Pennick, paraphrased.
The blue line is a little too high for Turned Shoulder Plane angle.
Usually it's drawn up through the armpit at address. (10-6-B)
The Standard (flat) backstroke shoulder turn component is meant to take it back to that line.
He's not far under it.
You have it at the Squared shoulder turn line, a much steeper plane. (10-6-C)
Hips too active, weight rolled to outside of left foot, loss of "left anchor", release could be delayed some more.
I don't necessarily disagree with your analysis of the line drawing . . . but I didn't draw the lines. Somebody else did . . . they were just on there from the site I pulled the pic from.
I do have a different take on the hips though . . . . look at the head . . . are the hips going forward or is the head backing up?
compare Hogan/Yoda to Graham. . . look at the tilt in the shoulders . . . Look at the difference in the straightness of the right knee . . . If you drew a plumb line from each players nose where would it meet the ground relative to the feet?