For about 6 months. From about November. Never used any chemicals on them however as I always believed they were detrimental. I did however remove the white gunk after showering each day which led to them getting worse.
I only began to leave them completely alone about a week and a half ago. This did cause them to look and feel horrific, which led me to believe it was a serious problem. However, by persevering this method definitely paid off.
My emphasis was leaving the crusts on for as long as possible. You need to imagine the crusts as a protective layer, allowing the skin underneath to gain enough strength to protect themselves.