The 24% more PRs was merged, not «landed». Presumably after human code review (but I didn’t check the paper…) Not sure about this particular study, but I «think» my own productivity (coding wise) has improved by more than 30%. In many ways I wouldn’t even have started on many of the things I’ve completed these last six months because I would have viewed their effort to be insurmountable within my time budget as a professor (with all my other duties).