What does the cryptic crossword clue "Might such rhetoric be no great shakes? (7)" mean?

The definition is "Might such rhetoric be no great shakes?". The wordplay uses a cryptic definition. Cryptic definition The answer is LITOTES.

Might such rhetoric be no great shakes? (7)

Guardian Cryptic #29305 | 19 Across | 2024-02-14 flower