Related Clues:

• First course?
• ''Nicely done''
• Course to start with
• Primary stratagem
• Primary course
• Initial strategy
• Preferred option
• First option
• Preferred way to proceed
• "Congratulations!"
• It's often backed up
• "Good job!" (and a hint to the beginning of 17-, 27-, 43- or 57-Across)
• Original scheme
• Preferred course
• ''Nice job!''