No, it's not the same as asking for evidence that circles don't have corners, because the latter is a strictly mathematical concept and the topic of promotion s

No, it's not the same as asking for evidence that circles don't have corners, because the latter is a strictly mathematical concept and the topic of promotion schemes is not. Can you provide empirical evidence with actual seniority based systems that match the very strict description you've supplied? Because if not what you have is an unsupported hypothesis, not a description of reality.