the elbows were bent in the video
Bent elbows is a compensation for the shoulder position
Torso tips forward is a compensation for getting in the overhead position
The heels come off the floor
The head pokes forward
It is damn near textbook of common faults in the overhead squat
100% lock out does not mean a compensation for shoulder position. If it did his external rotation couldn't be in that position. But as it were, his elbows are locked as much as his elbows allow.
Ever do a behind the neck press? Tell me where the bar path is at the top of the movement? Heels are not off the floor. If they were it would be an indication of the load shifting forward. Clearly it's not.
If you think those are "common" mistakes of the overhead press then you need to do some extensive research on O-lifts for athletes.....not Olympic lifters.
Common mistakes...
Anterior pelvic tilt causing the load to shift and the HEELS to come off the ground.
Lack of external rotation in the shoulders causing the head to NOT "poke" through. If the bar were directly over the top of the head there would be little if any thoracic mobility. Also, the lack of external rotation would indicate lack of scap and thoracic mobility and again, causing the load to shift forward. Ever attempt an OH squat and have your mid back cramp up while in full overhead extension?
Lack of dorsi-flexion in the ankles.
Hip disfunction
Vulgum
Feet that pronate or supinate
Head NOT being through the bar
Squat depth
THOSE above are the COMMON mistakes.