What if the brain operated more like a neural network than a calculator? Your second point seems to raise another, separate issue, whether or not knowledge gain

What if the brain operated more like a neural network than a calculator? Your second point seems to raise another, separate issue, whether or not knowledge gained can be applied in an unrelated context, or even if these two calculations would be performed in the same ways by the brain, such that training in one yields greater efficiency in the other. I'd wager that practicing hand eye coordination would yield greater efficiency in other task related to processing visual input, maybe video games.