That's clever, AB. At one point I tried for some sort of anagram with leader but didn't get the em / m angle!
I'll try another one in the same corner:
Periodical frost certainly reduced by electronic sensor (5,3).
- - - - - / - Y -
Something EYE? Not sure what though. Several phrases with EYE come to mind, like bird's eye etc but...what's an electronic sensor? A photo eye? Is periodical to do with Private Eye?