Pitkin's Postulate
If somebody approaches his level of incompetence with enough speed, he will tunnel through the barrier, and thereafter encounter negative resistance.
The Peter Principle applies to a great many people, but to relatively static jobs. For example, a good clerk may reach his level of incompetence when promoted to manager of clerks.
Pitkin's Postulate is the dynamic extension to the Peter Principle: it includes the most "important" jobs, those whose holders are in a position to do colossal damage.
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