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I mean, for me it would make some sense to make it sync with the block reward period which is 210000 blocks.
2016 is not a factor of 210000.
Was this done deliberately? Yes, of course it was, but why?
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Why did Satoshi not sync this to the block reward period and use 2000 or 2100 blocks(which are both a factor of 210000), which 2000 as most obvious round number.
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Regarding syncing with the block reward period, there was also some intent to avoid having both occur simultaneously to decrease the variability of having two events occur at the same block. It is almost always preferable to have one variable and everything else constant in a complex system.