Defect Seeding seems to be one of the few ways a development organization can tell how thorough an independent testing group is. I'm a fan of using metrics to help counter overconfidence biases, and drive discussions around facts. With that said, I haven't seen Seeding Defects used in practice.
Are there best practices above and beyond what McConnell explained? Are there public examples where this has been done? In the absence of the above, any thoughts on why it hasn't been done more?