What is the purpose of the redline documents in the contribution package

Contributors to the WS-RX tc, 

I am looking at the contribution package that was submitted to the tc.
It appears that both the WS-ReliableMessaging and
WS-ReliableMessagingPolicy docs also have their "redline" counterparts
in the package. 

Can one of the contributors clarify why the redline documents are there
in the contribution package? 

Cheers, 

--umit