Thought the oven handle was fine for years. Hung my towel there at every station I worked, never had a problem, so I figured the people bugging me about it were just being picky. Then I watched a towel catch on a 425 oven during a dinner push and the whole thing went up in about a second. Now it's the first thing I break for new people, towel goes on the rail or in your apron string, never the handle.

The 60 to 70 percent drop on the loose stuff lines up with what I saw when I ran my own test two winters back, so you are not imagining it. My setup was a little different, a Vermont Castings insert with about four seasons of buildup, and the CSL log knocked down the powdery flakes noticeably but left the shiny black crust untouched. What got me was how much softer the brush felt going past the smoke shelf, same as you described. I have to admit I laughed at myself after years of calling them snake oil because my old sweep told me the same thing your boss did. Sounds like both of you were right, it is a helper and not a replacement, and the folks who get burned are the ones who skip the real sweep thinking the log did it all. Thanks for actually testing it instead of just repeating the line like most of us do.