learning it

1. Around 10 yards before the mark (depending on line length, speed, etc.), pull the kites brakes on full. The kite slows down and de-powers. The buggy continues to the mark.
2. When you get to the mark, the kite will be almost stalled straight downwind of you, maybe a bit behind. It will the very twitchy and easy to steer.
3. Turn the buggy around the mark and at the same time release the left brake and apply right hand so the kite does a 180 degrees clockwise 'up' turn on its axis. (A 'down' turn works only for a big kite that has stalled.)
4. As the buggy completes the turn release the brakes to allow the kite to power out of the turn and accelerate you away.

when to use it

If you are holding a lot of power, have a kite that de-powers well on braking, and you want to avoid too much skidding on the turn..

When you are at the front of a bunch of racers rounding a mark. Your kite comes out of the turn low and so avoids the higher kites of your followers. See air at the mark.

It's nice so use as your 'normal' turn.

perfecting it

By varying the timing you can get a lot of different effects. Practice variations! For example on my Mosquitos, I find that when the wind is a bit light, I need to keep the breaking stage short and kite turn late, otherwise I have no exit acceleration.

A scrub jibe is also useful when you need to do a controlled turn, and so is often combined with a flat turn.