If you look at the SharePoint web.config file for a web application, you will notice the following section handler:
<section name="MergedActions" type="System.Configuration.SingleTagSectionHandler, System, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
Looking at the section you will see something similar too:
<Action id="fc002d03-7839-402b-a94a-1c9a2d40b63d" sourceFile="C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\config\webconfig.sps.xml" />
Then referencing the webconfig.sps.xml file, you will see that a merge action ADDS to your existing web.config file!
<add path="configuration/SharePoint/SafeControls" id="{FC002D03-7839-402b-A94A-1C9A2D40B63D}">
<SafeControl Assembly="Microsoft.SharePoint.Portal, Version=11.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.SharePoint.Portal.WebControls" TypeName="*" />
<SafeControl Assembly="Microsoft.SharePoint.Publishing, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.SharePoint.Publishing" TypeName="*" />
<SafeControl Assembly="Microsoft.SharePoint.Publishing, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.SharePoint.Publishing.Internal.WebControls" TypeName="*" />
<SafeControl Assembly="Microsoft.SharePoint.Publishing, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.SharePoint.Publishing.WebControls" TypeName="*" />
<SafeControl Assembly="Microsoft.SharePoint.Publishing, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.SharePoint.Publishing.Navigation" TypeName="*" />
<SafeControl Assembly="Microsoft.Office.Server, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.Office.Server.WebControls" TypeName="*" />
<SafeControl Assembly="Microsoft.Office.Server, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.Office.Server.WebControls.FieldTypes" TypeName="*" />
<SafeControl Assembly="Microsoft.Office.Workflow.Feature, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.Office.Server.WebControls.FieldTypes" TypeName="*" />
<SafeControl Assembly="Microsoft.Office.Excel.WebUI, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" Namespace="Microsoft.Office.Excel.WebUI" TypeName="*" />
</add>
So why do we have to worry about a web.config change if all the SharePoint Team has to do is modify the webconfig.sps.xml??? Hmmm...maybe someone didn't know about it in the design team?
Chris