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What happens if person does not bother generating PoS blocks for let's say 2 years? Does he or she gets the same PoS reward as persons who
were PoS mining every 30 days in same period of time?
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I think "coinage" is capped at 3 months. So, 10-month-old coins are just like 3-months-old. Waiting a year or two before starting up the client again will be missing the chance for some of the interest that could be generated.
Beyond that, much of POS are still quite mysterious to me.