I've just gone and removed semi-protections from about a dozen user talk pages. All of them were targets of vandalism in the past, generally due to their own anti-vandalism efforts. The pages included pages of administrators.
For obvious reasons, anyone who is warning and blocking new users in turn needs to be able to be contacted by these users with questions, concerns, etc. Semi-protection must not be used in this fashion, and I've removed the line supporting it from the semi-protection policy.
-Phil