Francis Phillips of the Catholic Herald has written a nice article in support of the immemorial custom of women covering their heads at Mass, basing her case upon the virtues of respect and modesty. In the course of the piece, she refers to the private correspondence of Cardinal Burke and its misinterpretation by Fr. Z (and Ed Peters and Jimmy Akin) for the proposition that head covering is no longer required under law.
This is why the making public of His Eminence's letter as well as the quick and dramatically unthinking spin on it was such a disaster. Words mean things, and when people with influence fail to conduct even the most rudimentary analysis of the actual words and context of such private correspondence before using it to score a public point it does real damage to the cause of Catholic restoration.
I have beaten this horse before, but let me try one more analogy.
Recall that Cardinal Burke is one of the foremost experts in Canon law in the entire world. He has a subtle mind. When he writes private correspondence, it is not meant to be public, yet he knows that someone might decide to make it so. Hence, His Eminence would likely choose his words with care.
Consider an analogy: a company writes a job description that requires the employee filling the position to drive to work in his own car. This same job description is published every time the position must be filled, over a period of many years. Once, due to lack of space in the newspaper, the line about driving one's own car to work is omitted. This confuses a job applicant, who had known about the company's longstanding requirement. But she knows one of the Directors of the Board for the company, and writes to him: "Does the job require that I drive a Mercedes to work?" The Director answers, "Nice to hear from you. No, you need not drive a Mercedes to work." If that letter were made widely known, would that stand for the proposition that one needn't drive their own car to work? Or just that it needn't be a Mercedes?
His Eminence's response to the writer was that, though it was the expectation in the Extraordinary Form, it was not "a sin" to participate in the Extraordinary Form "without a veil." To paraphrase St. Peter: "Are there Canon lawyers among you? For His Eminence is also a Canon lawyer. Then let them read." Veiling is not the universe of possible head coverings. What about hats? Or even, dare I say it, snoods? Are head coverings addressed in the letter, or just veils?
If you think that is too much of a strained reading, I ask you to pick one option, because those who are so desperate to conclude that head coverings are no longer required clearly want to have it both ways. Simultaneously, they wish to extol the obvious excellence and reputation of Cardinal Burke as a Canon lawyer for the proposition that we should adhere to what (they claim) His Excellence says, yet at the same time they will not give him the credit for drafting a letter well, as a Canon lawyer would do, choosing his words carefully and using them exactly. No, don't read the letter as though a Canon lawyer wrote it-- we all know what he means. Right?
So, the private, informal correspondence of a great Canon Lawyer is to be published, apparently without his permission, read as though he weren't a great Canon lawyer and yet the conclusion that does not strictly follow from the letter is trumpeted as though it were a binding legal decree. All to win the internet equivalent of a bar bet. And now the question is unnecessarily further obscured.
By the way, here is the article in the Catholic Herald.