On one of the CDs, Byron Katie mentioned that inquiry can undo lifetimes of material, and it certainly seems that way in my experience.
I see how I can play out these beliefs in my life, over years and lifetimes, and suffer the consequences until the situation finally becomes right for it to resolve – for me to see through the belief. Or, I can notice a stressful thought, take it to inquiry, and allow it to resolve that way. In a few minutes, I can do what would otherwise take lifetimes, or maybe years of exploration through other techniques.
The lifetimes of material seems true in a quite literal sense (without having to bring reincarnation into the picture). These stressful thoughts seem to be universally human, and have been with us since the dawn of civilization and probably before. They come to us through generations of humans, they have come alive in innumerable human lives. And now, they appear in us, inviting us to examine them and allowing them to unravel. They want their life, and they want to be freed from our belief in them.