When was the last time you practised or even just watched, setting up a mechanical advantage system? Mechanical advantage allows you to effectively haul (un-pin) large objects without too much mental and physical anguish. The usual suspects are the canoe or raft that got pinned on that rock as you flew down class III rapids, or even the shuttle van that ended up in the ditch somehow. As a high school French teacher of mine preached everyday in class "Pratiquez toujours Toujours, TOUJOURS!" As you could probably guess, this means "always practice!"
Practice makes perfect and when it comes to swiftwater safety the less time spent on the shore scratching your head the better. This is a great thing to do while waiting for you shuttle pick up or when wind-bound at a camp-site.
Here is a video from a partner of ours, Boreal River Rescue, which goes over the basics of setting up a mechanical advantage system and Z-drag. Please remember, this is no substitute for taking a course. If you have not taken a rescue course, there are a number of great organizations to work with (please see links below).