This is a really fun part of the course.  I really enjoy practice swims in class III slalom courses.  Picture this as kayaking at water level.  Here are some articles that provide some guidance:

• Strategies to conserve energy including positioning, short aggressive position sprints and “porpoising” for in-water scouting
• Defensive to aggressive transitions
• Aggressive upstream and downstream orientation (upstream ferry and downstream eddy catching)
• Crossing eddy lines
• Ferry techniques
• Managing holes and drops