Before abandoning the seniority system, we should ask people in other industries how promotions really work, not how they're supposed to work. Does the best worker become foreman, the most skilled "cutter" Chief of Surgery, the wisest professor Dean, or the finest legislator Speaker? I suspect that factors other than competence play a major role, and would be interested in hearing comments from those with actual experience in "non-seniority" promotion systems. We certainly don't want a situation where favoritism, deals, rumors, and back-stabbing become routes to advancement.