Ted - Did you ever resolve this Issue? What OS was running on the prod system? I have seen issues that appear to be the same as what you are describing (delays of 100-300 miliseconds for pooled connection resets for a system under load) on SQL2008 R2 / Windows 2008 R2 Datacenter (No SP1) and resolved the issue with the assistance of MSFT support by the application of this hotfix http://support.microsoft.com/kb/2155311

I'm currently seeing similar behavior on a different set of servers running SQL2008 R2 / Windows 2008 R2 Datacenter with SP1. Since this fix is included in SP1, it's not an option to apply it. Could be a regression issue with the service pack, maybe.

Was curious to hear your feedback if this was ever resolved on your end and if so how?

Thanks,

Matt