Possible Clues:

• Useless vibrato ruined voice in the end
• Checked in development conjuring with a bit over
• Failing to produce the intended result — a bit over, perhaps
• Fruitless
• Are a little fruitless in a boat I have
• Unsuccessful person on board, one tackled by furious voter
• A bit over-developed and not finally successful
• Failing to produce results
• Unsuccessful trio pulled apart by a book have to take a 50 per cent cut
• Steal show outside, returning fruitless