While the deliberate practice approach tends to focus on highly specialized training and purposeful techniques designed for improvement within a specific field, creative experts tend to have broader interests and greater versatility compared to their less creative expert colleagues. Simonton investigated all 911 operas composed by all 59 composers who contributed to the standard classical repertoire. If creativity were solely the result of deliberate practice, you would expect that the best approach for an opera composer would be to specialize within a particular genre of opera. But Simonton found the exact opposite. The compositions of the most successful operatic composers tended to represent a mix of genres. His data suggests that composers were able to avoid the inflexibility of too much expertise (overtraining) by cross-training. The importance of cross-training for creativity has also been found in the sciences. In fact, highly creative scientists tend to have a lot of artistic hobbies and interests. For instance, Simonton’s extensive analysis of Galileo reveals Galileo’s intense fascination with art, literature, and music. As the psychologist Howard Gruber has shown, rather than a dogged single pursuit of a single research question, the most creative scientists throughout history engaged in “networks of enterprise”, where they pursued a large number of loosely related projects.