scanafrica / Smilin Ed
If you (try to) get airborne, and fail, then of course there are measures that you or I might take in a desperate attempt to stay alive
However, that was not Smilin Ed's original point which was <<Why not fly it off?>> i.e. on every takeoff.
Your 500m remaining idea might be great... err except on those days when you are getting airborne within 500m anyway with a correct rotation
Or close in obstacles... or...
We have millions of successful takeoffs each and everyday using, in general, the correct rotation technique. Why endanger each takeoff to "cater" for the 1 in a few million times someone forgets something pretty fundamental?
Might I also suggest a read of the NW MD-82 accident report. Without Flaps/Slats the aircraft would climb ~41' in ~5000' from Rotation - correctly configured it would climb 600'. The only solution is to configure the aircraft correctly, not just "try and fly it" with whatever Flaps/Slats you find yourself. IMHO
NoD