| LETWELLALONE | Don't try to improve on a perfectly good water supply? (3,4,5) |
| STET | Is, at best, deficient in odd places? Don't try to improve it |
| RESERVOIR | Earmark without sweetheart, trip to Rio over good water supply (9) |
| UTOPIAN | I put on a perfectly good disguise (7) |
| AMEND | Improve on a repair (5) |
| GROWING | Good water sport on the up |
| AZURE | Like good water for snorkeling |
| UPGRADE | To improve on transport, a prude overcomes gravity (7) |
| REVERSEENGINEER | Take apart (a device) in order to improve on or copy |
| FICTION | Establish falsehood insider concocted to improve on narrative a lie |
| GALE | Patrick ?, author of the novels A Perfectly Good Man and Notes from an Exhibition (4) |
| ICANEXPLAIN | "There's a perfectly good reason for this" |
| GETAHEAD | First task when staffing new school is to improve on schedule (3,5) |
| PULLONESSOCKSUP | Strive to improve on luck -- losses disastrous in what swindler's sold one? |
| ENOUGHTOMAKEA | Sufficient to improve on the Cheshire cat's grin (6,2,4,1,3,5) |
| CAT | Sufficient to improve on the Cheshire cat's grin (6,2,4,1,3,5) |
| LAUGH | Sufficient to improve on the Cheshire cat's grin (6,2,4,1,3,5) |
| DUNCESCAP | New College blocking fees to improve on fool's mark |
| BREAK | Opportunity to improve on sequence of strokes in pool? (5) |
| GENERALLY | DNA to improve, on the whole (9) |
