Wow. I was in the middle of working on a blog post about message construction and the Business Rules Engine (BRE) in Biztalk 2004. Several other Biztalk Developers and I were talking about this topic at Tech Ed and at the BPI Conference. I looked at Richard's Blog and he posted an excellent post on the exact same topic! At first glance, it looks like the BRE changes an immutable message or does it...