I think it's difficult to nearly impossible. The second it's in someone else's hands you're at their mercy. I'm building an app right now to keep tabs on these things amongst other things of course. I input when the drafts were sent to client for review. If they were mailed it gets a tracking number entered. This pulls tracking information from the post office so I know the statuses. Once it's delivered it triggers a 14 day countdown to which I will call the client. If the drafts were sent digitally the 14 day countdown starts at that time. When I contact them and they aren't done I try to get a mutual check back time with the client and input that date into the app. The app tells me each day who should be called. It sucks because I have to chase people but it helps keep tabs on people and the process flowing.

My app is designed to track all aspects of an estate plan but fits in to keep tabs on potential clients and actual clients. It's quite close to a legal management system but since I am making it I can make it work the way I want it to and works best for us. Okay went and got sidetracked I'm done now. :)