Thank you Giles Greenwood
Lots of people examine the technique of great lifters and look for what's different about the way they lift.
I find it instructive to see where these lifters techniques are similar as well as where they differ. Some positions might look different at first glance but still share many similarities. For example, Chinese lifters tend to have a more upright start position than European lifters. They look quite different but apart from the feet pointing out a bit more and the knees being pushed out they're actually very similar - shoulders over the bar, bar roughly over the joint of the big toe, back flat etc. You can use the knowledge of the differences to adjust your lifters positions according to their strengths. The knees out start position emphasises leg strength while slightly higher hips/toes forward will use a bit more back/glutes/hamstrings.
I think there is surprisingly little technical variation in the key positions. Start position has variety, bar at knee height and power position are pretty standard then the finish position has some variety. No "tricks" that the best lifters know and we dont' (as far as I can tell anyway!), just correct technique applied extremely well by strong people.