I can't even think about functions 5-8. They seem pretty esoteric and not all that well defined.

How's this for a theory about whom to turn to when trying to strengthen fourth function weaknesses:

A person with an area of primary first function strength will be less adept at teaching this strength since it comes naturally. A person with the area as a second function would be best, since greater practice and development has gone into that area.

What does everybody think?