If you can't trust the pool operator, then all systems have potential for abuse.
I had avoided adding bitcoinpool completely because of its Draconian measures designed to fight pool hoppers (rather than changing reward systems). Of course, as hopping becomes more prevalent, you can expect more pools to go down this road. Hopefully, they'll have to become so awful that users won't want anything to do with them, but I don't have high hopes in that regard. Users seem willing to tolerate a lot of abuse.
I have a hop function for bcpool's 50-50 tax that you can use if that helps, Aexoden.