Nobody seems to have noticed that Stilton introduced the third type of Takeoff, i.e. The Roll-On Takeoff, where the aircraft commences the Takeoff with it's existing taxy speed. As Stilton suggests that it should be, it IS considered as equivalent to a Standing Start Takeoff, provided that the existing speed is at an approved minimum (usually 10 knots).
The Rolling Takeoff commences at Zero speed, and differs from the 'Roll-on' Takeoff in this respect. It IS approved (and usually recommended) provided that the Various Field Lengths are reduced by an approved amount (usually 60M or 200ft) before making the RTOW calculation. This can, in Field limited circumstances impose a significant reduction in RTOW, in the vicinity of 5% is not uncommon.
Best Regards,
Old Smokey