What does the cryptic crossword clue "We dart and tear around, but don't make any progress (5,5)" mean?

The wordplay uses an anagram. anagram of WE + DART + TEAR = TREADWATER The answer is TREADWATER.

We dart and tear around, but don't make any progress (5,5)

Guardian Cryptic #24406 | 14 Down | 2008-06-04 flower