The best info we have at the moment is that -- generally speaking -- if you run your chlorine at 10% of your CYA level, you will lose about the same chlorine, regardless of levels. Put another way: you'll lose about the same amount of chlorine daily if you maintain FC=3 if your CYA=30, as you will with FC=8 and CYA=80.

However, there is some unconfirmed information that suggests that you will lose less at very high FC/CYA levels (FC=15; CYA=150). But even if that info is correct, the improvement is not huge.