It's a shallow article on well worn territory. This is the closest it gets to touching your assertion > A number of line managers told me they gamed the system

It's a shallow article on well worn territory. This is the closest it gets to touching your assertion > A number of line managers told me they gamed the system. They would put people who had just joined the team in the bottom bracket, because they were easier to sacrifice. Or, perversely, they tried to hang on to poor performers so they could put them at the bottom and protect everyone else. You are correct though, we have no way to accurately measure knowledge work. I'm a broken record on this, all performance management is subjectivity masquerading as objectivity. It's making work about work that doesn't make the org more effective and in fact is toxic. There are too many examples from the past 40 years across industries for anyone to claim ignorance.