I just watched the vid of the 2010 World Champ posted by Proparc and noticed that he used a semi-wingover to shut his engine down at the time and position of his choosing.
I've heard about pilots doing this to make sure they touch down in the ideal spot relative to the wind and judges, but rarely observed it for myself.
Anyone care to comment on the usefulness of this, whether they do it themselves or not and where exactly on the circle you're aiming for things to happen?