Expand DNS Privacy Considerations?

[bumblefudge]

@TelegramSam made a great point today that "phone-home" is a trending meme and a (not always precisely or scientifically) applied rubric of evaluation, and after discussion on today's meeting, it was suggested that the "DNS Privacy Considerations" section should probably:

• Explicitly remind the reader that a webvh DID doc is self-certifying, so can be trusted whether resolved directly, via a cache, via a CDN, via a watcher or "VDG"-style trusted watcher+resolver service, etc
• Dmitri mentioned that the HTTP Cache-Control header might be worth suggesting as a configurable way of reducing traffic that goes "all the way home" where CDNs and the modern internet can cache (also just good engineering for latency anyways)
• Make clearer that verifiers MAY use privacy-enhancing technologies to resolve, and hosters/publishers MAY support them on their side