While the vinegar bath might have helped, it's fixing the symptom and not the root of the issue. Your chimney has too much draft for your stove. In order to fix the plugging cat issue in its entirety you must reduce draft. Obviously Bholler wasn't using technical terms when he said ash would get sucked into the cat. Obviously the chimney is not a blower and cannot suck in anything, however we don't always speak in technical terms, and you clearly understood the message he was trying to convey. I understand that you believe that you are operating the stove perfectly for your needs, however you are not operating the stove as the manufacturer intended or in the most efficient manner for heating your home. Maybe you should try some of the suggestions on this message board, you never know, you might get your stove dialed in better than you thought possible.