No No.... I'm not talking about immersing the pipe or licking the outside of the bowl either. Cork the
bowl and shank.... Use some good common sense.
Why would you want to remove wood from your pipe? I would think again before using an abrasive like sand
paper or steel wool. If it has a couple of dints you want to get out, raise the wood back, don't sand it.
Put a wet washcloth over the dent and heat it with an iron or heat gun. The steam will raise the dent back
up. The dent is just compressed wood. Now if it's 'missing' wood like a scratch, it wont work.
I don't know a lot about furniture refinishing but have refinished a bunch of pipes. I don't know that there would be any harm using the Formbys on a pipe if used with --as TopD said--a little common sense. But I won't be using it on my pipes. Don't think it is necessary. If a pipe has a lacquer or other type of varnish on,I use steel wool damped with alcohol to remove it.Soaking the bowl in alcohol will speed the process,although I usually don't do that.
The lacquer on a pipe is there for two reasons--to make it shine without a lot of sanding and buffing--and to hide the sanding scratches. Most lacquered pipes are sanded to about 360-400 grit,not high enough to give a nice shine.
If you remove the lacquer,you WILL have to sand it to at least 600 grit to get a shine--if you have a buffer. If no buffer it will have to be sanded to much finer grits. This is where Micro-Mesh is nice. It will put a nice shine on a pipe with enough elbow grease as long as you take your time and and make sure it is well sanded before moving up to the next grit.It is possible to put a VERY nice shine on briar with out wax.
To remove the stain( on a un-lacquered pipe),an alcohol soak will get most of it out,sanding will be needed to get the rest and even then you will be lucky to get it all unless you remove quite a bit of wood. Removing stain WILL NOT make a pipe smoke cooler as removing lacquer is supposed to do. The stain is in the wood--not on it- as a lacquer is.Soaking in alcohol will raise the grain somewhat,and will give the briar a soft,kinda fuzzy look. It will require buffing at a minimum and maybe sanding and then buffing.
Steaming dents out sometimes works.Depends on how deep the dent is.Quite often I will steam then sand to completely remove a dent.
If properly done,sanding the pipe to remove dents and scratches will not remove a lot of wood. You would probably need a micrometer to measure just how much was removed. I usually start with 400 grit.If that doesn't do it I back up to 360. Very seldom is it necessary to go any courser than 360.With some pipes you may be able to start with 600 or even 800,depends on how smooth or scratch-dent free the surface is.
While wet sanding ain't gonna hurt the briar it is best to sand it dry. The water will raise the grain making it hard to get a nice shine.