Originally Posted by Sheldon Brown
The average tension on the chain is no different with a Biopace chainring than it is with a round or elliptical ring of the same size.
If that's you main concern, go for big rings and sprockets. Better yet, make sure they are even numbered and keep the chain/sprocket phase relationship constant.
See:
http://sheldonbrown.com/chain-life.html for details on this.
Sheldon "Live Long And Prosper" Brown
Now we're getting closer to the OP. So you're saying that the force on the chain is equal regardless of when it is on the high or low point of the BP CR?