A few years back I stumbled upon a term that illuminated my understanding of why some metaphors fall flat. I have waded through the muddy waters of the Internet and have no seen neither hide nor hair of the elusive term. It has truly become my white whale.
I don't remember if it was a term from literature or psychology, but basically it was a term used to describe why a statement like "she was trying to thread an elephant through the eye of a needle" does not make sense to people who do not know what a needle or an elephant is.
The phrase above does not actually describe what I'm looking for. The phrase I'm looking for has to do will me using a metaphor to describe some personal discovery. For instance, someone finds a novel solution for a long standing problem. When asked to explain how he came find the new solution he says "I thought of the problem as wanting to boil a pot of water. After that it was simple." When the problem at hand had to do with physics or engineering. Thinking of the problem as "billing a pot of water" has nothing to do with the problem and noone else sees the connection, but it let him glean some insight that helped him solve the problem.
The term I'm looking for had to do with "the boiling put of water" having some significance to him that other people can't understand since they did not make all the thought gymnastics to have that view point.