When i flew from melbourne and Sydney, I needed my bags ASAP at Sydney as i had a meeting to get to. I asked the Lady at the counter if she could put a Priority Bag tag on my bag. She told me, even if she put that bag tag on it wouldnt do anything because the baggage handlers just scan the white airport code tag on the bags and thats how they sort it.

possibly it might make it easy for the handlers by seeing business class tags, Maybe the tags are just to satify us FF who fly J or F Class or are high FF.

Just my 2 cents and my experience

Regards,