This is my new favorite cleaning utensil. We run cleaner through the KBTS Technivorm that we use in the warehouse every week or so - to clean the water reservoir, filtercone and carafe. I admit to being fascinated by the gunk that comes out. When I then scrubbed the carafe with this hooked brush with the hot cleaning solution still in it - I got out even more junk!
Maybe there is a bit more pathology here than usual - but cleaning your coffee equipment is a must. Your coffee will not taste right if you do not clean the brewing equipment and containers. This makes getting into the curved spaces of carafes a bit easier.