2) Swim By Tune Up Drill

The Swim By Tune Up Drill is a great drill to run with youngsters just out of swim-by in basics as it extends the swim-by concept to the field scale.
It is also useful to maintain "water mindness" in advanced retrievers.
Remember to focus on treading water with each whistle stop prior to casting to swim-by. Treading water is an important skill in water blind retrieves.