Jay Honeck wrote:
How does this buy you an extra several hundred feet of runway?

If executed correctly, the Sylvania Swing means that you'll be hitting
the start of your takeoff roll already going 20 knots or more.

I must not be visualizing correctly what you are talking about. I was
thinking it was like a J laying on its side with the long leg being the
runway and the short leg being beside the runway (assuming a pretty wide
takeoff area). You start point away from the direction of takeoff and
then make a sweeping turn onto the runway. However, if you do that wide
enough to be at 20 knots when aligned with the runway, you will have a
fairly large radius of turn and I'll bet you lose nearly as much as you
gain.

Matt