I have not seen the term Net Takeoff Distance used in any of the manuals I'm familiar with here in the US.
The FAR's define takeoff fild length as the longest of these three distances:
- Engine-Out accelerate-go distance
- Accerate-stop distance
- The all-engine go distance which is 115% of the distance required to:
- Acccelerate with all engines operating
- Lift-off
- Reach a point 35 feet above the runway surface at the all engine climb out speed.
Don't think I answered your question but that's the way the FAA looks
at this subject.