Failing to match URI in SWITCH statment

I don't believe you want the "starts_with" operator as part of the switch. You probably want something more like this:

when HTTP_REQUEST {
   switch -glob [HTTP::uri] {
      "/argo/tcc*" {
         use pool one
      }
      "/argo/tc-update*" {
         use pool two
      }
      default {
         use pool three
      }
   }
}

Notice I added -glob to the switch command to enable glob matching and then added an '*' after the strings.

For more information on the switch command Click here:

http://tmml.sourceforge.net/doc/tcl/switch.html