Assume you have 100 eMu at a value of $100, the market value isn't moving at all, the system isn't even attempted to stabilize it, its naturally stable at this point. Assume it stays this way for a year....your 100 eMu are still worth $100...0% ROI. However demand for eMu is high, so the system is creating lots of new eMu to absord the incoming value from fiat, gold or whatever else you decide to use. Assume that inflation over the year is 100%....you will receive 50 more eMu over that time (its a 50/50 split between hatchers and balance holders). You now have 150 eMu worth $1 each, 50% ROI.
I think these would be considered wages (income), not ROI. It is payment for work, not investment. The interest paid might be considered ROI. I suppose if the distribution is based on *all* previous work performed, then early adopters could get progressively higher wages (a larger cut of the distributions), but this might be disturbed by a flood of new workers entering the system (assuming they each are paid something for the smaller amount of work they've performed).
Anyway, this is a bit off the cuff. I'll look into it more.
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If the coin takes off, the early adopters could potentially get huge payouts as massive minting is stimulated. Yes, they are wage slaves, but gilded ones like wall street workers with their lavish bonuses.
But new workers would rush in, perhaps diluting subsequent payouts. Depends on the exact algo used.
Also, bitcoin has long periods of stable price. emunie won't need to increase supply during these periods, so I'm presuming it will pay nothing, a potential problem.
A very interesting experiment to watch when it goes live.
BTW, if I work for the system for some time, then sell my coins and quit, will my prior work still qualify me for payouts, i.e., can I retire to the south of France with my emunie pension?