Financial Times Chinese has a good article about the importance of a broad knowledge. The title is "Forget focus, celebrate breadth" You can find the Chinese versino here.
As the name implies, you are suggested to have a broad knowledge first. I totally agree. Again, Chinese has a old sayinga about the best way to build your knowledge "Broad and extensive first, then go profound and in-depth". Based on my experience, I had developed a "theory" to prove it.
We all know that the brain works as a network. Many interconnected cells that may form many different type of sub-networks that interconnected naturally and magically to form the brain. It's a networked intelligence. Scientist already proved that by focus on different type of study/knowledge, different part of the brain/sub-networks can have a better development or more active. That means stronger interconnection within the subnetwork.
So by having a braoader knwoledge, more subnetworks or more parts of your brain can be developed. Now here is the cool part. I think anytime you read something or heard something from someone else, this "new" knowledge will hit your brain like a bullet going through many networks. The more network this bullett can hit, the more "reaction" will happen between thsi new knowledge and your existing one. A perfect chain reaction. I think that's why research also proved that the more messy a person's office/house is, the more reactive/innovative this person will be. Why? a broader knowledge and more broad network his brain may have, though the network maybe quite light (not deep knowledge), but this person can generate more new ideas because of his broader brain.
I believe my creativity benefited a lot a lot from my reading of the Can Kao XIao Xi, a great newspaper in China that has broad international news, in my junior high school and senior high school year. I like reading every page of the newspaper, till today. I think every piece of reading or knowledge is useful, it's just a m ateter of time about when you may use this knowledge. Building your arsenal now by reading extensively...