I agree, the calculators are BS. As I write this the next estimated difficulty increase is < 9% not the 20% everybody thinks will continue forever.
bitcoinwisdom.com/bitcoin/difficulty
It will not continue forever, but it continues for a very long time:
http://mining-profit.com/bitcoin-difficulty-historyAnd why should it stop? What you think? Major miners still have cheap electricity and a lot of new mining hardware
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take the best machine power wise on the market an sp10 in low power mode does 1th at 700 watts no machine is better then .7 watts a gh. you to need spend 3k if you are lucky to get one. I did 10 cents a k watt that is cheap . no cooling cost (not realistic) 421 a btc .
so the most efficient machine know to man needs a 9% diff rate to make a few bucks if you get 10 cents a k watt and cool for free.
This translates to some slow growth. Or big price cuts in gear .
at 20% a loser
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at 15 % a loser
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