From what I understand, dry-burning weakens the nicrome wire gradually. It was originally introduced as a "resurrection" method, to bring back atties which were almost dead or barely alive. Some people today use it as a part of regular routine maintenance. Most manufacturers advise against it but many people seem use it successfully. I've dry-burned many atties in the past and a few times but only when they are really on their way out and not really usable since there is a risk of completely ruining them if not careful.
I would rather not do it often. This one seemed dead. this brought it back.
Hope you have a good one!