Why cant the luck stay around 100% for a while. Why from 192% straight down to 40%

Almost like the Texas weather, from one extreme to the other in a day.
I suspect something is wrong still with slush's pool from the problems we had on Friday. Only 5 blocks found today.. My backup pool which has a less combined hashing power than Slush found 17 blocks for the day so far!!! What is going on?
