Establishing Position is very important for several aspects of the game:
Having mastery over position will enable a handler to replicate that position quickly and often, leading to the kind of consistency that is required for the dog to actually learn the skills we are teaching them. Without this kind of consistency, setting up and disc placement are hit or miss, which means that there's possible safety problems as the dog may get confused as to what is being asked of him.
Practice makes perfect, right?
Wrong.
Perfect practice makes perfect.
There are few things that are as big a turn off for a discdog team as confusion and difficulty in setting up. If the dog and handler can't hook up quickly and efficiently, practice suffers. This puts undue stress on the team as they struggle to get ready to work.
Having solid positioning will make practice far more successful and fun.
Being able to quickly and efficiently establish position is extremely important to creating a flowing routine.
It is frustrating as a handler to try to get a dog into a set position when the dog is not able to accomodate the handler on this request. The entire flow of the routine can be destroyed with faulty or inefficient positioning.
Here are some videos of position training.
First with treats: