KIAmen,
The first thing I thought when I read about Xp/Agile was that it was justification for hacking. But once you use it you realize how good it is.
And as funny as it is, I have been on waterfall based projects where all the reporting to management by the PM was based on waterfall but what was really being done was more of a crappy agile process that more closley resembled hack 'n' slash because the people doing the actual work including software leads know that there are deadlines to consider.