Good question! The main benefit is you deploy directly from your git-server to your production server, instead of uploading from your own computer. This means a lot faster deploys, especially when your deployments are large or your internet connection is really poor (being able to make deployments quickly while on a 3G connection is awesome). whiskey_disk uses one ssh connection to your server for all work (so less time for spawning ssh connections), and the heavy traffic is not to/from your local machine.
Other benefits of the tool include putting all config files into version control, and a lot less less magic in your deployments.
Other benefits of the tool include putting all config files into version control, and a lot less less magic in your deployments.