How? In my understanding Advani was not born to a Brahmin family & I never found him joking at brahmins.You think brahmins will be that stupid to get in your trap. Forget about brahmins, no caste or race group (except commi/congi/chmchas) in India will fall for such trap.
Advani openly suggested Modi's name as PM at his book opening ceremony. It is for everyone to see.