Possible Clues:

• Most significant worker in force
• Functioning; worker
• Prove a tie looks odd for a manual worker
• To choose, I have to include age for worker
• & 14 Emphasis on this promise from labourer?
• Working in musical theatre, the writer's keeping time
• Significant poet I rave about
• Worker's work time - time given without limits
• Back-to-back shows, lacking a skilled worker
• Worker working on musical show nearly backed another