The concept of productive thinking was first proposed by German psychologist Otto Selz in the early 1930's. Selz's work was unfortunately cut short in 1933 by the rise of Nazism and anti-semitism. Until recently, very little of his work had been translated into English. Later work under name of the Productive Thinking model was put forward by Canadian author Tim Hurson who proposed a structured approach to solving problems or generating creative ideas. This structured approach combined knowledge with creative and/or critical thinking. A successful and effective productive thinker can be both fully creative yet also fully critical of the results of their creativity.
An example of this might be an author who writes from their heart and imagination but yet can go back later to what was written and honestly critique the style, and the flow of the narrative, the vocabulary and punctuation towards improving the end work.