There is no reason passenger handling, security can not be done at Mascot with the passengers being bussed in secured busses direct to the airside at Bankskstown. It should enable some flights with smaller aircraft to be handled from there meaning cash flow and some happier passengers. It does not mean everything can be done that way but a little may help.
That's the second stupidest idea I've ever heard.
Every 'solution' bandied around so far is nothing short of a totally pointless exercise, which has no intent other than giving an appearance of doing something which needs not be done anyway.....total WOFTAM.
You could probably stand in the middle of a puddle of AVTUR and throw a lit match into it too, and it would not do anything. But, I don't see any particular reason to test that equally stupid idea either!