Inverted minors means that if partner opens a minor, a raise to two of the minor shows ten or more points. A jump to three of the minor shows a playable hand with less than ten points and no four-card major. The principle is to bid slowly with points and to bid quickly when weak to take away the bidding room of the opponents.
Depending on vulnerability, three of the minor could be very weak. When vulnerable, six points is the minimum and at favourable vulnerability (opponents vulnerable and you not vulnerable), a couple of points with shortness is the minimum.
The bidding: South has a balanced 14 points. He plans to open one club and rebid one notrump. With one more point, South would have opened one notrump.
North has a weak hand at favourable vulnerability and jumps to three clubs. East and West are unable to enter the bidding to find their heart fit. They can make three or four hearts.
The Lead: West leads the ten of spades, top of a sequence.
The play: South wins the spade continuation and draws trump. He will lose one spade, two hearts and two diamonds. South will be down one. This is a victory, not a defeat, because the opponents can make at least +140 in hearts and had to settle with +50.
North Raises to Two Clubs:
If North raises to two clubs, South will pass and West will balance with a double. East will bid and play hearts, either at the two-level or at the three-level depending if North or South competes in clubs.
South will likely lead the king of spades against a three heart contract by East. East will ruff two clubs in dummy and will pitch a losing diamond on the ten of spades after trump is drawn. East will lose two spades, no hearts, no diamonds and one club, making four hearts for +170. With a diamond lead, East will make one less trick for +140.
Result: Three clubs by South down one for -50 or three hearts by East for +140.
-We have seen how inverted minor raises solve the problem of investigating major stoppers.
-We have also seen how the opponents can be shut out of the bidding with a three club call.
-All the bridge columns may be viewed at http://watsongallery.ca.