Possible Clues:

• It's no good giving you tea in a paper folder
• No good to see 17 across for this
• It's useless to have it on the roof at last (6)
• Useless, a waste of effort
• A waste of time
• Useless, producing no results
• It's quite useless to put it in the fuel
• It's useless to put it on the wall at the bottom
• Ineffectual, unavailing
• In vain, a waste of time