Agreed! In Miss Manners' Guide to Excruciatingly Correct Behavior, she says that "'Mrs.' with a lady's first name is always incorrect" (p. 809 in the Kindle edition) – and the whole issue arose because of the LW's first name! Of course, Miss Manners does always note that if someone expresses a preference for, e.g., "Mrs." in all circumstances, that should be honored even if it's not technically correct. But I was surprised to see her seemingly giving the imprimatur to "Mrs." with the woman's first name, especially when "Ms." is so standard in a business environment.