Some of our performance issues - particularly around DFS-R namespace resolutions used when navigating a W2k8 folder structure - appear to be related to the fact we do not really have "enough" DC's/domain controllers for our distributed environment. However, all of our local sites are covered by Steelheads.
I believe DC traffic is encrypted by default which puts it out of the reach of Steelhead optimization, but I'm hoping there's some future magical answer for such situations without breaking encryption ... just as there has been for other encrypted traffic.
:)
