This is sort of a special case because it wasn't previously a documented feature or something that (IMO) was ever used by anyone. My feeling was that if someone happens to be using this I'd rather just have them get degraded behavior than have a compile error or exception when running their job.

In general this is not a proper deprecation because actually we are removing the functionality not just giving a warning.

Wrt the other question, I think we'll probably follow semver http://semver.org/ which says you have to give a full minor release w/ the deprecation warning before removing it.