A style of trad climbing used at very highest levels of difficulty where a fall is almost certain to be fatal.
The climb is practised on top-rope until the climber is wholly certain that they can climb the route without falling. The route is then climbed without falling or resting on protection, from the ground up and an ascent can be claimed by the climber.
The term is only used at the highest level of trad climbing, for example British grade E8 or higher due to the uncertainty or unavailability of protection combined with a high probability of death should the climber fail to climb the route making it necessary for the climber to get it right in their heads before attempting to lead the route.
As not many climbers wish to to finish their days as a broken greasy splatter amongst the boulders on the ground ethically the method is as sound as any other type of climbing as long as the climber is honest to the media and other climbers about the methods used to gain the ascent.
At this level of climbing initial failure is certain, so death or bad injury is certain too unless the route is thoroughly practiced safely, the moves memorized and dialed in to the climbers head. The climbing can be recognized as a distinct type of ascent due to the fact that despite the climber having successfully climbed the route on a top-rope they will have to do a technically difficult climb along with the psychological pressure of knowing that to fall is to be hurt badly.