By RAH, Infinite Flight ATC Supervisor:
When flying on Infinite Flight, with ‘Straight Out Dept.’ in the current ATIS, aircraft are expected to maintain runway heading until no conflict exists; after which, departing aircraft can proceed on course.
This is a more simplified version of what is used in the real world. Multiple Infinite Flight ATC Supervisors commented that it was simplified due to the complexity and different variables that come into play if things such as Standard Operating Procedures (SOPs), minimum offsets based on runway compositions, ect. for example, were brought into play.
1. 7.1.6 of the ATC Manual (PDF), retrieved on June 28, 2019.