Mike Griffin seemed to see his Constellation program as viable only if it had as little new technology as possible. New technology, though it would result in greatly lower costs in the long run, might lead to delays and overruns in the short run. (Never mind that the old tech led to delays and overruns anyway.) Politicians also want to prevent any innovative tech that might be built in a different district or state than theirs. These sorts of anti-innovation forces have become a real problem for NASA : The Value of Innovation - citizensinspace.org.
Jeff Foust on the White House response to the petition to double the NASA budget: A penny for NASA? That’s what that petition was worth. - Space Politics.