Miss vs. Mrs.

An article on politeness in the Economist, subtitled "Life is getting friendlier but less interesting. Blame technology, globalisation and feminism", reminded me of one tidbit of info that I stumbled across:

[B]oth “Miss” and “Mrs.” were originally shortened forms of the word “mistress.” The modern sense of “mistress” implies an illicit relationship, but before about 1600, a mistress was simply a female head of a household—married or unmarried. As a result, the abbreviation “Mrs.” would originally have been pronounced “mistress,” and would not have been used exclusively to refer to someone’s wife. The pronunciation “misses” was simply a contracted form of “mistress.”

- Excerpted from Interesting thing of the day

I've heard some decry the substitution of the address "Mrs." with "Miss" as a terrible consequence of feminism. Yet, (a) historically they come from the same root, and (b) it would be in line with historical usage to refer to an unmarried older woman as "Mrs."