I think its more of a matter of adding it to the earnings when its not real. Still the only time this seems to happen at hashrefinery and ahashpool is if they end up on the wrong side of a fork. It's rather aggravating seeing the earnings just drop all the time.
Both pools you mentioned have fairly safe variance of coins whereas zergpool mines coins that are still mostly new or not available on other autoexchange pools. or plainly unstable in terms of price, which is why estimates are... estimates.
People just have to learn how things work.
And atm we need zergpool to work, had to move all my miners after a hundred retries...
https://i.imgur.com/2EDNB1m.png