Also, I don't see it mentioned, that he reason one uses such potent alcohol is because the water content is so low......if the briar absorbs water it can be damaged. I have a friend who damaged a pipe with 50% isopropyl. So it has low h2o, and evaporates quickly.
As to the salt treatment: Essentially you remove the pipe's stem, and plug the shank with cotton, a q-tip, paper towel, etc- then fill the bowl with a "rough" salt- sea salt or rock salt. Then the salt is saturated with high proof alcohol such as evercleer or 90+% isopropyl- and this is allowed to soak for several hours. The idea is that it leaches out nasty ghostings and flavors from the bowl. After several hours the salt will be brown and nasty- dump it out, clean it up with some pipe cleaners and there you have it.
Care must be taken not to spill the alcohol on the outside of the bowl. Most people use a syringe to apply alcohol to the salt.
Chris