Guarding personally identifiable information

As the author, I appreciate the thoughtful comments about my analogy between de-identification and encryption. I think the analogy is better than gdt and frostsnow think, but perhaps they are right. If you don't like the analogy, just take the general principle that the perfect is the enemy of the good, and that something is better than nothing. I'm also glad to see that the main controversy in the comments concerns a relatively minor point within the larger article.