I think it's rather sad and of course gamey at the same time to get so much BB reduction for assassinating/killing your own court members, especially babies.

I keep a large court now just for BB reduction, I marry my oldest daughter outside the realm and the rest I marry within the court to keep a nice long list of babies to slit their throats (grrrrrrrissquissssssssssh) muahahahahaha. I still offer up Bishophroics for the piety bonus vs BB reputation, but, assassinating court members is the fastest way of reduction I have found and I get to keep ALL the claims I get during a war and don't have to play the 1 for 3 claims game like others have mentioned.
Even though it would ruin my gameplan don't you think that assassinating your own court members to reduce BB reputation should be reduced or even removed???