So basically the cause was one or more of the following:
FUPool works on their own blocks after they see other pool blocks if they are found soon after.
Wow, I would call this an exploit. It would gave them the ability to mine until the next block is found by the network praying they will get the next one to screw the orphan race they lost for the previous one.
I hope this is not the case
that's the one that is truly gaming the system. not sure they did it but if it were to happen over and over and over it is flat out wrong.