[Working on an article–here is a draft of my introduction. What connections have you observed between legalism and mediocrity?]
The ultimate result of legalism is mediocrity—a willingness to do the minimum, a lack of motivation to go beyond that which is required.
Perhaps you have seen this quote from Alexander Solzhenitsyn:
“A society based on the letter of the law and never reaching any higher, fails to take advantage of the full range of human possibilities. The letter of the law is too cold and formal to have a beneficial influence on society. Whenever the tissue of life is woven of legalistic relationships, this creates an atmosphere of spiritual mediocrity that paralyzes men’s noblest impulses.”