Anders Wirgren-Johan Bennet (Cavendish winners -91, Bermuda Bowl bronze -95) have been opening 1C with 5M332 routinely a number of years now (11-13/17-19 bal/semibal or clubs). They have a choice of opening bids with this pattern, but 1C is the predominant choice with minimum hands (only 1M if suit is 'rebiddable').
Not opening with the major gives you 2 ways to win. For me, the primary benefit is that you can use this to your advantage as responder knowing that opener has better playing strength/shape when the auction gets contested (i.e should you make a negative X or how high should you raise with support?).
The secondary way to win is that it's frequently better to initially just show hand-type (bal/unbal) before suit(s) and this way your choice of developing the auction means that you'll get a bigger edge if the opener becomes declarer as less is revealed to help defenders.
By having a choice of opening bids, you give yourself the freedom to exercise your judgement but you take away the, in my view, primary edge.
Anyways, Anders sent me this deal from an outing in Denmark, showing us edge no 2 in all its beauty...
Anders was South and opened 1C, Johan transfered to 1NT and then raised to game. West led the J of diamonds.
Low from dummy and RHO won the king and shifted to the queen of H (!). Anders won and attacked clubs to the queen and king. East continued his attack on hearts and the low heart return was ducked to dummy, with West discarding. An easy +430 when the majority of the field were 2 down in 4H.
Will this way of treating 5M332 catch on to a wider audience?