http://agroff.github.io/posv/ ya read this
Ok so I think I have it sorted out, it is pretty simple to understand once you have worked your way around Reddcoins own technical PDF.
In layman's terms it works like this:
PoSV Proof of Stake Velocity
They designed the system to reward people not only for having a stake in the currency but for actively using the currency which encourages the economy of the coin. If it was all about how many coins you had the coin would be hoarded instead of used as currency.
Velocity means that the older your coin is the less it will stake, so a coin that is 4 weeks old will reward much better than a coin that is 10 weeks old. I think it 1/2's each time the coin stakes or earns.
This means that you not only want to stake volume of the the coin but you need to keep them young to ensure they are rewarding you at the highest stake.
Thats how I understand it. I could be wrong and welcome someone to explain it better.