With the requirement to modify configuration Files for web services, tracking those changes in the .config file can be tiring.
Clean things up using the configSource property to organize and track changes.
When ever you change any settings in your .config file take the time to pull out the section that you are modifying into a new file and replace it with configSource property.
For example, in a web.config for my WMS service I have modified the "<appsettings>" section to include "<add key="forcePNG32" value="true"/>" So I copy the entire appsettings section to a new file I call appsettings.config and make my change.
<add key="forcePNG32" value="true"/>
Then modify the original web.config file by changing the appsettings section to "<appsettings configSource="appsettings.config" />".
It is now a lot easier to determine by file date etc.. what has been modified and on what date.