Update news post to clarify.

doc/_posts/2013-12-12-capnproto-0.4-time-travel.md

@@ -20,6 +20,12 @@ arrive at the client at the point in time when the call was originally made!
 Curious how Cap'n Proto bypasses the laws of physics?
 [Check out the docs!]({{ site.baseurl }}rpc.html)
 
+_UPDATE:  There has been some confusion about what I'm claiming.  I am NOT saying that using
+promises alone (i.e. being asynchronous) constitutes "time travel".  Cap'n Proto implements a
+technique called Promise Pipelining which allows a new request to be formed based on the content
+of a previous result (in part or in whole) before that previous result is returned.  Notice in the
+diagram that the result of foo() is being passed to bar()._
+
 ### Promises in C++
 
 If you do a lot of serious Javascript programming, you've probably heard of