Women's hair covering

Question

I listened to your radio program in which you discuss women's hair covering. In it you say that there is no heter for a married woman to uncover their hair. Granted, this is what most poskim held, but I am sure you know that the wives of many great rabbanim from Russia and Lithuania didn't cover their hair. There was a view that in modern times, since most married women are accustomed to go uncovered, that today it is mutar. The Shulhan Arukh states that a woman's hair which it is the practice to keep covered must not be shown. One could say that if it is the practice to uncover it, than it is mutar -- even if the first people to do this were sinners.