Possible Clues:

• Drawback, having to follow behind wretched vehicle — long to get round
• I'd upset unhappy Head with mark: E minus!
• It¿s a drawback for Sidney and father to come back with a good view of something
• Navigated badly, circling wretched albatross?
• Dad navigates criminal stumbling block
• Unfavourable position
• Unfinished record by The Edge is a stumbling block
• Flaw — weak point
• Draw Back for detective's benefit
• Prima donna accepts unhappy agent is upset by loss