Is the question not clear enough or to tough?
It's Clear to me and from what I have heard it is not possible, the client always checks it's cache, then a peer, before going to source as a habit of the agent. I would rather have that changed to where if I want the package to come from the server and not a peer then it listens and does so.
I have also searched to no avail. Its not there
I think that the packaging/deployment system needs to be rethought slightly.
At the moment there is to much knowledge needed for a Servicedesk agent to deploy applications. They need to know if special requirements exist for the software they are deploying - Run from source, etc
What I would like to see is the ability of the Deployment packager be able to specify what deployment methods are available, and be able to configure them. Maybe have different tabs on the package for each of the four main deployment methods. Each tab can be enable/disabled by checkbox, and the fields in the tab would be used to provide specifice. Then if a package needs to be deplyed by a Service desk agent they just need to know the computer, the package and when to deploy (if its a push install).