Essentially, their argument was that this would be a huge pain and expense to fix, and so we are all better off just keeping it on the down low. And that kind of worked, for about a hundred years, until more open communities - like computer security research - started looking seriously at locks (as both metaphors and as interesting mechanisms in their own right).
I see their point, even if I personally reject it. But in the age of the Internet, you just can't keep this kind of stuff secret.
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