Possible Clues:

• Stray American soldier turning up in uniform
• Wander from the point to make taunt about ship
• Leave the point
• Wander about before start of supper in hostel?
• Go off the subject
• Deviate from the main subject
• Be sidetracked when groom holds serving man up
• Turn aside (from the main subject?)
• Stray from subject
• Go off at a tangent about son in lodgings