Instructive and accomplished performance in charge (8)
I believe the answer is:
didactic
'instructive' is the definition.
(similar in meaning)
'accomplished performance in charge' is the wordplay.
'accomplished' becomes 'did' (doing is a kind of accomplishing).
'performance' becomes 'act' (act is a kind of performance).
'in charge' becomes 'ic' (abbreviation for 'in charge').
'did'+'act'+'ic'='DIDACTIC'
'and' acts as a link.
(Other definitions for didactic that I've seen before include "giving lesson" , "Edifying" , "Teaching morally" , "'Instructive, perhaps excessively so (8)'" , "Instructive, perhaps patronisingly" .)