Found this article on ausbt.com stating that Oneworld airlines are no longer required to check luggage through on separate bookings. Very annoying when you have no choice eg Amex 2-4-1 which only allows flights on BA metal so no choice but to make a second booking for onward travel.

http://www.ausbt.com.au/did-oneworld-just-make-your-next-trip-more-of-a-nightmare?utm_source=internal&utm_medium=flipper&u tm_campaign=home-flipper