Hard to tell some changes with camera angle changes. No need to upload in slow motion, it makes it harder to see actual timing, like I'm pretty sure you are slowing down on your x-step instead of accelerating or gliding thru, or not slowing down.
1. Not a fan of towels. For practice swings, just hold your disc sideways wing up and fan the air out of the target, instead of swinging the nose down.
2. Rear foot still looks pigeon toed on the x-step leading with your toes, instead of the heel first like Simon.
3. Start in more neutral posture like walking natural. Looks like you are trying to start in a static position instead of getting into position dynamically. Like you are trying to walk while starting in a running position, instead of starting from a natural standstill position and then getting more athletic/dynamic as you increase speed. (Watch my x-steps timestamped toward end of Swing Drills vid, I'm much more upright at the start and flowing into more dynamic position) Your head is hanging too far over your toes and pulling you over and making you do other compensations for being out of balance like your huge left arm swing back. Try to keep your left elbow near your left hip the entire time, let the lower arm swing.
4. Start and finish your whole x-step and throw Inside the Wall (Inside Swing Drill). Put your first right foot step toes on the wall and make sure your head doesn't hit the wall and don't punch the wall with your left arm or shoulder, while following thru all the way.
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