I find it an anoying and pretentious little phrase, I suppose partly because I don’t know what it means or where it comes from.
I heard it in a Placebo song, and it the name of a column in the Sunday Times magazine.
No cite, as my dictionary of phrase origins is at work, but AFAIK it comes from the sport of boxing - if you’re “boxing clever”, you’re using your brain and wits rather than brute strength, and thus you stand a chance of beating a stronger, but less quick-witted, opponent.