Can I use Rational ClearCase or ClearQuest in place of Team Foundation’s change management features?
You certainly can use another source control or work item tracking systems in place of Team Foundation’s corresponding features. In some cases, you may find that the integration between a third party tool and the other Team Foundation features is not as rich as with a full Team Foundation environment. We are actively encouraging other tool vendors to leverage the integration and extensibility features of Team Foundation to bridge this gap.