The author tries to mislead the readers. Although continuity of culture and tradition may have contributed to some extent, other factors like Education and the flexibility of people to accept/adapt to other cultures have become more important for development. In fact, I think education is the number one factor - this contributed to the development of Chennai as a powerful center for quite some time, however, the inflexibility of people in the far southern states/cities in accepting other cultures/languages undermined their economic importance, and the rise of Hyderabad (which lagged in education but picked up fast) and Bangalore which happened to be more flexible in terms of acceptance and adaptation to new cultures/people.
