Fair point, that was badly phrased. I'll try and split out what I know for sure.
The BRAS and the MSAN both hold a line profile, and both are based in the exchange. I've seen speed test results that don't tally with the profile seen reported in WCR, so I know that those bits of kit are (or can be) independent. The only bit I'm unsure of there is which kit reports to which system.
There's also the fact that the diagnostic systems we have access to allow us to run a consistency check test that reports on the profiles on the BRAS and MSAN, and will advise if a mismatch is found.
Those things I do know for definite