This is going to sound like a silly question, but I'll explain.
What exactly does query duration (such as found when running a trace) include?
Is it just how long the engine takes to execute the query, or does it also include how long the resource sat in the UMS queue and/or time to put in the return buffer and/or time to return the data to the client and receive acknowledgement from the client that it received the data (and/or other steps in the process)?
I ask because I'm seeing some interesting things with wait stats that don't necessarily depict what I'm seeing in a trace. Any help here is greatly appreciated. Links to sites describing the lifecycle of a SQL Server request are also appreciated. I've not been able to find these yet.