Answer. The basic concept of bridge is communication that is done through bidding. Different systems have been evolved over the years, which prescribe different bidding methods to convey the pattern and strength of each type of hand from one to seven level. The idea behind is to settle at the optimum step of the contract. Here the question relates to offering a jump bid of two in a suit over one no trump (15-17) opening bid. All the systems lay down a standard scale of good point count, quality of suit and distributional value to qualify a hand to make a jump bid. Because a bid of that kind, first of all guarantees a game contract and secondly, strongly suggests an attempt at slam preferably in the nominated suit. The range of high card point or distributional value with good suit is 13 to 17 with a good trump suit to try for a slam and anything more than that paves a way to a grand slam.
For the hand with the range of 10 and 12 points is good enough to score game in no trump or in a major suit with somewhat solid holding. In this case there is no need to make a jump bid, because there cannot be slam ambition with that range strength and the suitable game can be reached by applying Stayman convention to play in a major suit.
There is a provision for partnership understanding in making a jump bid with lower range also. But that has got a barricading value to keep the opponent from entering into any bidding and at the same time limiting themselves to game level. If the responder bids further beyond game then it should be understood that he has a hand with higher rage of point count for a slam try in no trump or a suit contract. But invariably in all situations the nominated suit is required to be good 5 or 6 cards headed by top honour cards. The bridge textbooks as well as experts are in agreement for the requirement of a jump bid in a suit that is in question here. A few examples are given below to further illustrate the point: -
If the partner opens the bidding with one no trump, the following holding perfectly fulfills the requirement of a suit jump bid in spades:
The above examples are mere suggestions as to the point count and distribution of cards to show the self-sustaining trump suit in spades to offer a jump bid. There can be many more combinations of cards that may qualify for a jump bid with the game and slam interest in mind. But a responding jump bid of two in a suit also is considered as trump determining suit, hence it has to be good suit with touching honour cards. The partner of one no trump opener should, never consider a broken suit or a suit headed by only Queen or a Jack, for a jump bid in any situation excepting in response to takeout double over opponent's opening bid.
It is hoped that you will find the answer to your question with a brief explanation given above satisfactory. And any suggestions or questions on the subject by a knowledgeable player like you would be welcome for the benefit of bridge players in general.
Golden Tips: A sound comment is a healthy instrument for improvement in the game.
1. S AkJ987 2. S KQ10978 3. S KJ10976 4. S AKQ109
H K108 H K 5 H KQ 9 H QJ10
D QJ9 D J108 D AQJ D AQ98
C 6 C A10 C 9 C 4