Well this is a good question. In the past, shaft packings ran without shaft packing lubricants. The question is, what is gained by the use of a shaft packing lubricant on the replacement packing? The lubricant reduces the friction between the shaft and the packing. This means less mechcanical wear of the packing. The less mechcanical wear of the shaft against the packing means longer packing life. Longer packing life translates to longer time between packing replacement……fewer haulouts. The reduction of friction between the shaft and the packing could also translate to better fuel economy. Commercial workboat owners have found that by using a shaft packing with a lower surface friction they end up with better fuel economy with their vessel. Commercial owners do this by using very high tech w.l. gore shaft packings. The same as our gtu. If you elect to use a non w.l. gore shaft packing, you might consider investing in a good shaft packing lubricant to reduce the surface friction. One of the best is called syntef. It is available at most marine supply outlets.