Not heard of it happening for real. Maybe someone will know. Cindy?

Practice it, takes very precise flying by the tow pilot. Speed control and rate of descent control. Aim long or you're dragging the gliders through the weeds before the runway. Tow pilot does not brake unless he is running out of runway. Glider goes to low tow, keeps the rope tight with spoiler. Much easier in a draggy 2-33 than a Grob or K-21.

BillT