add comments from sunjay

Author: mark-i-m

src/traits/specialization.md

@@ -43,6 +43,9 @@ known concretely.
 
 ## Additional Resources
 
-[This talk][talk] by @sunjay may be useful.
+[This talk][talk] by @sunjay may be useful. Keep in mind that the talk only
+gives a broad overview of the problem and the solution (it was presented about
+halfway through @sunjay's work). Also, it was given in June 2018, and some
+things may have changed by the time you watch it.
 
 [talk]: https://www.youtube.com/watch?v=rZqS4bLPL24