Possible Clues:

• Roy Hobbs (with "the")
• The twist of a turn with the half of a century in the nature of things
• Instinctive - not surprising
• Taking a turn involved a number as expected
• Created without human assistance
• One born with sporting talent
• Relaxed, unaffected
• Unrefined person certain to succeed
• Expert despite little training
• Turn somersaults around a boy? That's normal