Where's the response?
I couldn't figure out why I was not getting an immediate response. I ran through my code several times before I realized I was missing a key test at a crucial decision making point. I was failing to check whether or not the ManagedThreadPool in my application could get to my request now or whether the request would be pooled.

ManagedThreadPool.ActiveThreads < ManagedThreadPool.MaxThreads - 2

Simple as that. A simple test in a more complex if statement. Why the - 2? Well, I needed a margin to allow for the fact that other threads would be jamming their own jobs in. So I figured a margin of 2 unused threads would give me that. We'll see how it does in the real world.

Lesson Learned
If you plan to use a thread pool, be sure to pay attention to how many babies are in the water at the moment you decide to jump in. Otherwise, you may not get what you expect when you expect, especially in a system like I have been working on where hundreds or even thousands of items might be queued up.

(Note: This is being reposted because I inadvertently allowed trackbacks and the previous post got hammered with spam trackbacks and dasBlog would log me out when I tried to go to the post to delete them. Go figure...)