@Bass/@evildictaitor: But, again, we're talking about buying/using a product, TFS.
I didn't mean to suggest one might find it easier to create their own TFS alternative using open source (code). I meant the very issue highlighted is sometimes so great that I am forced to consider and select a readily available, quality, open source product, e.g. Subversion; even when I believe TFS may be the better (technical) solution.
I don't know Dr. Herbie or his company but if I hear I must involve the lawyers, my evaluation is over. I'm looking for something else.