It says there can be as little as 2 miles of separation which I read as 2 miles when the wheels lift off begining acceleration would end up with 0 ft of separation.
Just to keep stating this: I'm not at all defending the AUS controller here. A squeeze play like this in low visibility is needlessly reckless.
[1] https://www.faa.gov/air_traffic/publications/atpubs/atc_html...