Possible Clues:

• State again specifically limiting train's highest speed
• Repeat line ignored by educated person
• Repeat one note with speed
• Linguistically proficient learner's avoided repeat
• Last-ditch
• Learned without learner provoking stress
• Continuously improve, in tech-speak
• Learned head missing -- say again
• Sex charge embracing sweetheart? Say again!
• Once again, go over most of renegotiated treaties