In this section I am going to dissect the 20-21 NT opening and game opportunities for the partnership. When applying the computer simulation data, please make adjustments according to hand evaluation and opponent bidding. I am not going to discuss slam opportunities because it is usually fit oriented and control oriented and you must find that out in your bidding system and not just pure HCP, or HCL or HCLS points.
There are also many different styles of 20-21 NT opening / response partnership agreements. I am not advocating any specific one. Since I only want to do analysis on one style and I choice the one I use. No 5 card major. No 7 card suit. No restriction on doubletons. I believe the result of including 5 cards major may be different in the % of games made due to higher % of a major game. Other style may not have any significant effect on the %. All data in this section uses about 4 million deals and 8 million partnership hands.
First of all let me start with a simple table of probability.
There are no surprises here. a long minor suit increases the value of the NT hand. This is especially true for slam hands.