Massive non-issue.If there is one thing I have learnt from my travels to stadiums all over the world, it is that building multiple large stadiums in the one precinct is a logistical nightmare. It means you can never have events at both sites at the same time, as moving 120,000 to 160,000 persons through the same area at the same time causes all sorts of issues.
Imagine 100,000 leaving the MCG and 60,000 arriving at the proposed Swan Street / Gosch's Paddock Stadium at the same time, the majority of which would be using Richmond station as driving in the area would be impossible.
The beauty of the olympic park area is its walking proximity to multiple trian lines, as well as the CBD. 100k + 60k would be the absolute worst case for back to back sat/sun games. Reality is, if one game finishes at 4pm and the next starts at 4pm, then most people will have cleared 15min before first bounce, and before the first game's crowds come back.