Not an expert by any means, but yes, I do it when smoking a pipe sometimes. I tend to do it sporadically a few times throughout the bowl, But not all the time. It also depends on the tobacco as sometimes it can bring out a nice spicy or peppery note, other times there is very little change and other times it can be bitey or have too much of a sting. Can't really explain how to do it other than you expel the smoke out of your nose rather than your mouth. I don't think I have ever tried it with a cigar as I learned about retrohaling after I had kinda gotten out of cigars and into pipes.
