Letters Free-Enterprise Builders Unfairly Blamed To the Editor: As a free-enterprise builder in Southwest Ohio, I read your December "Miscellany" article with some apprehension about the true purpose of Operation Sly Fox. Frankly, it sounds like a concerted union effort to discredit and antagonize builders who prefer not to align themselves with trade unions. It is my observation that irresponsible builders exist on all levels, but the underlying blame there in Illinois seems to fall totally on the "non-union" builders, which of course cannot be true. Are you so uniondominated over there in New England that it colored your perspective? By the way, I would suggest you use "free-enterprise builder" rather than "non-union builder," which is derogatory and infers that we somehow are not