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I say that because I don't imagine the developers being ready to increase difficulty/reduce block rewards at a perfect 1:1 ratio against the increase in hash/s
Nonononono. This is totally wrong!No one increase or decrease the difficulty! There is no one behind bitcoin, there is only MATH. Developers can only watch, that's all what they can do: watch, nothing more.
Difficulty depend on total hashing power
And reward is reduced after a certain number of blocks, roughly the number of blocks found in 4 years