Air-Gap System Deployment

Everything I've read indicated that MCC must be deployed on an Internet connected system.  However, Microsoft Copolite said it can be deployed on an air-gap (i.e. closed, non-Internet facing) system and to use the pre-seeding tool to download contents.  My main interest is to use MCC to assist with future Windows OS upgrade and (secondary) patching on my closed network.  I currently pull-down patches via a connected WSUS and then sneakernet them over to the WSUS servers on our closed networks.  Has anyone successfully deployed MCC in an air-gap environment and operating as intended?  Any lessons learned?  Thanks in advance.