According to my speech therapist, proper huff coughing is not the problem in long-term cases (she has been working for 23 years, many of them with a pulmonologist who specializes in bronchiectasis.) She told me years of coughing and rough throat clearing damage the trachea and often the vocal chords. Breaking those habits over the past 7 years and replacing them has been very hard for me.
I am finally "almost" there. I have learned to keep my allergies controlled, sip liquids, do breathing exercises and suck on pectin-rich lozenges to keep my throat moist and soothed. This minimizes the clearing. And to stop myself as quickly as possible of hard coughing begins and switch to controlled breathing and huff coughs. These have taken about a year of practice and consciously interrupting myself to "do it right."