20 / NOTRUMP OVERCALLS [06.30.2007] IMMEDIATE 1NT [15-18 HC  -  "SYSTEMS ON"] 2NT [UNUSUAL for 2 Lower UNBID Suits] 3NT [FINAL] BALANCING 1NT [11-14 HC  -  "SYSTEMS OFF"] TO-X Followed by 1NT Rebid [15-17 HC] 2NT [19+ HC  -  "SYSTEMS ON"] 3NT [FINAL] "SANDWICH NT" "LHO" Opens PARTNER Passes '"RHO" bids 2nd Suit NT OVERCALL [Competitive for TWO UnBid Suits]