Similar tricks can be played with the human brain, things we have been able to do for decades, while people are undergoing brain surgery, and now later, with TMS. However, being able to elicit limb movements or bits of speech, or even emotional qualia is different from having a dynamic understanding of the brain in vivo in everyday life.
Certainly having an understanding of detailed circuitry is interesting and important, but to me there's a forest for the trees problem.
I really hope we can realize how the whole thing works by looking at its parts. But I doubt it will bring the breakthrough. On the other hand maybe there is this one mechanism that we have to discover to make sense of all the parts. Then those efforts will form the groundwork for an explosive understanding.
This made me realize we may one day willing allow human brain controls to get us to do things we don't want - Work, Exercise, etc.
We already have that: coffee.
I find that as we gain new tools to study the nervous system more specifically, both data and models of how neurons are organized at the circuit level become more important. To advance on an analogy in the article, it's like trying to explore the dynamics of NYC without a map. For instance, it's hard to tell how/why people interact with central park if you don't even know where they live. The more specifically you are able to pin down people, the more it matters where exactly they live to understand.
Granted, the fly is much simpler than humans or even mice, and it will likely take decades and new tools for us to study humans in this way. However, when we get there, mapping out the brain connections will be crucial to make sense of it all.