The Modern Jump shift by responder bidding 2 ♥ on a 1 ♣ or 1 ♦ opening
This convention solves the issue of the responder that has 5
♠ and 4
♥ after the opener rebids his opening minor . Without this convention he has no possible secong bid with fewer than 10HCP :
- Bidding ♥ on the second round would be a 3rd suit forcing bid
- a 2NT bid would require 11HCP...
- The responder knows that the opener may have 4 cards in ♥ , but he has to pass!
With the conventional Jump shift to 2
♥,the opener knows precisely the hand of the responder and can decide accordingly !