Too inept to move like a ballet dancer, perhaps (2,6)
I believe the answer is:
on tiptoe
'like a ballet dancer perhaps' is the definition.
(a ballet dancer might move on tiptoe)
'too inept to move' is the wordplay.
'to move' is an anagram indicator.
'too'+'inept'='tooinept'
'tooinept' is an anagram of 'ON TIPTOE'.
(Other definitions for on tiptoe that I've seen before include "How to sneak" , "Ballerina's position" .)