Possible Clues:

• Head introduces Rilke, a simple task
• Hardly rocket science, underwear lacking rein for adjustment
• Trivial matter head doesn't need to be bothered with
• Straightforward choice
• Head back, returning around home, which is easy
• Head in rare confusion - this shouldn't cause it!
• Aristocrat, one of April's eight, far from rocket science
• Nut rare in crumbly piece of cake
• Aristocrat finding Rilke an easy job
• Something requiring no mental thought