I slowed it down and put it in wireframe. Without vertex weights the shoulders still look perfect. There are a few vertex in the hips that are problematic but from the looks they could be fixed if parented to thigh rather than hip.
For the extra code and processing time required for weighted vertex I think better evidence of it's benefits is still necesary.
For the extra code and processing time required for weighted vertex I think better evidence of it's benefits is still necesary.