Hello Daniel Cohen-Dumani,
In the 4.5.4 version of RadEditor for MOSS the Strip All Formatting option is called "All HTML Tags". In order to enable the FormatStripper in the RadEditor you to make sure that you have the following line in the respective ToolsFile.xml (ListToolsFile.xml for forms cenarious), which is located in Program Files\Common Files\Microsoft Shared\web server extensions\wpresources\RadEditorSharePoint\184.108.40.206__1f131a624888eeed\RadControls\Editor folder.
|<tool name="FormatStripper" />
You can find an online demo of the old version of RadEditor in the following locatino http://demos.telerik.com/aspnet/Editor/Examples/Default/DefaultCS.aspx
And here is the online documentation for it http://www.telerik.com/help/aspnet/editor/howtofind.html
I hope this helps.
the Telerik team