Resident Evil 4 beta version - in-depth analysis

Resident Evil 4 sure did change a lot before we actually got to play it. Much like Resident Evil 2, the game was given a major overhaul before it hit retail. Just what happened during development that lead to such a huge shift? Perhaps the beta details can fill us in on why some changes were made. All I know is, we wound up with a fantastic game after all the tweaks!