Cleverly effective (4)
I believe the answer is:
neat
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cleverly effective</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for neat that I've seen before include "Tidy - old cow!" , "well-kept" , "Shipshape" , "Tidy, well-ordered" , "Tidy - orderly" .)