In the Land of the Blind, the One-Eyed Man is King. -- Erasmus.What makes an expert? Two things: Can-Do and “Proper” Interest.
Interestingly enough, Can-Do is not necessary. In a community of ignorant people, the least ignorant might be identified as an expert, provided someone has sufficient and “proper” interest in what the “expert” supposedly can do. The dilemma of expertise is this: only a real expert knows enough to recognize others as real experts. The “experts” of everyday life are usually those whom influential ignoramuses designate as such.
“Proper” interest is most important because “really trivial, disgusting or shameful” things – things your Mom and Dad warned you against – are supposed not to invite us to admire “expertise.” For example, there are, amongst “well-brought-up” people, no recognized experts on sniffling, or on growing toenail fungus. Nor are there “experts” at musical flatulence.
The 'gator hunting expert of Flamingo, Florida is an almost nobody in Cambridge, Massachusetts. The Schlegel expert from Cambridge is not anyone special in Flamingo. Such are the joys of diversity.
An important corollary: people seen as threats are not usually recognized as “experts” by those who feel threatened. Annoyers, disrupters and damagers are usually not bestowed with the honorific title, “expert,” no matter how skillfully they annoy, disrupt and damage.
Should schoolteachers strive to be experts? Maybe not. Let's just focus on the teachers, who, because of their skills, actually cause the learning they intend. In the minds of some, such truly expert teachers would have a potential for disruption. They could affect the demand for goods and services. If they convince their students not to smoke or to watch less TV, in the long run they might undermine whole industries. Such teachers might expose children to "dangerous" knowledge!
Students might come to realize that their sex appeal is not enhanced by imbibing quantities of Coke or Pepsi, or by paying twice as much money for designer labels sewn conspicuously on their clothing. Profits might fall and jobs might be lost.
In addition, truly “expert” teachers would be in a position to communicate radical ideas, for example, respect, or concern, for persons different from oneself, that might -- in someone's opinion -- "take us down the path to (whatever)ism." In short, the more expert teachers are, the greater the possibility for both economic and social upheaval. So many people might want to forget about developing teacher expertise. It is safer to let them muddle along and leave the real world to its own devices.
"Education is a weapon whose effect depends
on who holds it in his hands and who is struck with it."-- Joseph Stalin
To examine these issues further, see What Can a Teacher Do?