16:32 Jul 19, 2010 

I can actually articulate why it may be stylistically unpalatable. It is only good when your baseline assumption is that all communications must be encrypted, and when you encounter something that is not, it comes to you as a shock -- then you call that message "unencrypted". It is a powerful school of thought, and it rules in some domains. But encryption is a burden that most of us don't want to shoulder with our own resources, so a more prevalent baseline assumption is that all data are sent in the clear. This assumption makes "unencrypted" sound heavy-handed, almost like "unabnormal".