WHOIS Privacy Protect -- What Spamfighters Think

As others have mentioned, a recent court ruling suggests that when accompanied with "intentional spamming," hiding who owns a domain behind a "privacy protect" service (such as Domains by Proxy) could mean that the sender is in violation of the CAN-SPAM law. But let's set that aside for a moment. Even if there wasn't a potential legal issue, do recipient systems and anti-spam groups find privacy protect to be a reputable practice? Let's ask a few smart anti-spam experts what they think.