Add areas of focus to editors.md

editors.md

@@ -2,6 +2,8 @@
 
 Below is a listing of Solid Editors. See [Reviewing Proposals](README.md#reviewing-proposals.md) for an explanation of how the editorial process is used to review and accept changes to Solid Specifications, the Solid Roadmap, and Supporting Documentation.
 
-| Name      | WebID      |
-| --------- | ---------- |
-| [Tim Berners-Lee](https://github.com/timbl) | [WebID](https://www.w3.org/People/Berners-Lee/card#i) |
+Areas of Focus identify where a given editor can be expected to provide editorial review. These are not designated rigidly because there is important value in editors being able to review changes to Solid that might seemingly be outside of their direct areas of focus. For example, an editor whose areas of focus include security may have important reasons to provide review on a spec tied to interoperability. At the same time, editors should know enough to abstain when they can't provide informed editorial review. If something isn't part of their areas of focus, or if they haven't spent time getting educated on the substance by the authors of the material, they should abstain.
+
+| Name      | WebID      | Areas of Focus |
+| --------- | ---------- | -------------- |
+| [Tim Berners-Lee](https://github.com/timbl) | [WebID](https://www.w3.org/People/Berners-Lee/card#i) | As Solid Director, timbl has broad oversight across any and all things Solid. |