Possible Clues:

• Obstinate exercise by last defender is noted by lineman
• Bolshie salesperson possibly coming up with lines
• A biblical extract that's intractable
• Bolshie traveller coming up with lines
• Wrong, how bard might be paid?
• Obstinate agent turning up with lines presented in book?
• It's not the norm getting agent back to Limerick
• Peculiar proposal for paying poets?
• For each part of poem is difficult
• How poets are paid?