When we preempts the bidding they cannot have 3 or 4 keycards. So it does not make sense to have a keycard system that shows these. Here we look at an improvement in steps and in how we ask.

When Opener makes a jump shift into a new suit with their second bid, it is a strong bid that creates a game forcing auction. This is a good bid because it ensures we reach game, but it is a bad bid because it eats up a lot of bidding space without fully describing our distribution. This is a problem. One of the most difficult opening hands to describe to partner is the unbalanced single-suited (one 6+card suit) hand with 18-19 HCP.  This is one of the strongest hands that does not open the bidding 2♣.  With this hand we usually open our suit at the 1-level and after partner responds at the 1-level, we lie in a minor suit.  If our one suit is a Major, then we show our strength by making a jump shift into 3♣, even when we have very few ♣ (as few as 2 cards.)  With this bid we create a game forcing auction (showing our values), but we distort our shape (partner expects that we have at least 4 cards in the ♣ suit). This can cause some confusion with partner if they have a large fit for our ♣ suit.  We would like to have a way to let partner know that this jump shift is done on a single-suited hand, not on a two-suited hand.  Let’s look at a system that helps us improve our jump shift methods.