One question to ask is then: what method is useful to figure out the function of an unknown microprocessor? The engineers sometimes reverse engineer chips with

One question to ask is then: what method is useful to figure out the function of an unknown microprocessor? The engineers sometimes reverse engineer chips with electron microscope, with a perfect understanding of electronic principle, a rudimentary idea of how the microprocessor works, what the high-level function of the chip is, etc. And even equipped with this knowledge cracking a chip still takes a lot of effort, and may not succeed at all. The tools of a neuroscientist would be laughable in comparison, yet neuroscientists have cracked the auditory code (and you can have an artificial cochlea now), the lower visual system is close to be cracked, we have a pretty good understanding of hippocampus and how space is represented in the brain, and many other accomplishment. These are all results from the laughable tools we have for investigating brain. Having a full connectome of the brain, and running the brain in a simulator will be a huge step of understanding it. We don't know how to use the data now simply because we don't have the data yet, and therefore no effort is putting on interpreting the data. However the usefulness can be glimpsed from neural structures where the connections are clear: the peripheral system, spinal cord, midbrain, and lower sensory and motor regions in the brain. We understand them far better than regions we don't even know where it connects: claustrum comes into mind. A simulator of the brain, I imagine, will be similar to the human genome project: nobody will understand the whole thing quickly, but it will hugely prop neuroscience forward, sometimes in ways we cannot imagine now.