5) "Independent" cost estimates for Constellation systems are cited. There is no acknowledgement that these are low-fidelity estimates developed over a matter of weeks, yet are offered as corrections to NASA's cost estimates, which have years of effort behind them. ...
I'm not sure why Dr. Griffin surrounds the word Independent with quotes. The Aerospace Corporation is independent of NASA. Therefore, its cost estimates aren't as subject to optimistic thinking or internal pressure and censorship as NASA estimates of its own costs. Note that other independent sources (for example, see The Budgetary Implications of NASA’s Current Plans for Space Exploration by the Congressional Budget Office) have also been skeptical of NASA-only cost estimates. This skepticism is based on a long history of budget overruns on NASA programs. Here's a recent quote in the Kansas City Star on the NASA Science side of the house:
As for the scientific missions, "We're really blowing it on our cost estimates," said Marc Allen, a planning manager in the space agency's Science Mission Directorate. "Everybody's motivated to paint a rosy picture."
Could this be the case within Constellation too? Let's have an independent assessment to find out.