Perhaps I'm missing something here, because I'm not entirely thrilled with this system.
As I understand it, there is an upper limit on payouts to prevent miners from statistically profiting from pool hopping. However, the value you've earned beyond this upper limit is banked by the pool and used to pay out more on longer blocks.
Does this mean that the only way to fully drain 100% of your mining earnings from the pool is if the pool encounters a string of long blocks, forcing the pool to pay out your 'banked' earnings?
In other words, if the pool is lucky (lots of short blocks) then the pool limits payouts and holds the profits. If the pool is unlucky, then you can be paid out for your actual earnings. This limits the miners' upside and only gives you your total earnings if the pool is unlucky anyway.
I guess my concern stems from the fact that there is an upper limit to your payouts, but no lower limit. And the only way to completely drain your earnings from the pool is to wait for a string of long blocks to drain your 'banked' balance and then quit mining.
Are you going to pay out this 'banked' balance after a certain period of inactivity, or do you keep it for the pool/yourself?
Wouldn't it make more sense to only force this system on miners who aren't mining for 100% (or 95% to account for connection problems, etc.) of the duration of the last x number of blocks?