heart wrote:I am sure the same is true in Bon.
True indeed. The one given by TW is a simplified version based on the Ma-rgyud practice. There are other styles of this practice, including that of the Phyag-khrid, that of the Kun-bzang 'khor-ba kun-'dren, etc. Some are simple to the extent of being very very unelaborated (with only a very slight movemen of the hand and fingers closing the nostrils) and others involve yogic movements, similar to that one finds in the six yogas.