The effective leader does not just train a replacement; the effective leader instills his own DNA within the replacement. This is more than instruction; it is impartation.
Proximity is key; there is no substitute for “being together.” Before every activity, the leader should ask two questions: (1) Can someone else do this (delegation)? (2) If not, can I do this with someone else (impartation)? You do the latter until you can do the former.