A small, but essential modification of the Lebensohl convention, applicable for the Fast or the Slow variation as well. If you're already familiar with Lebensohl, all you need to do is to remember that this is an acronym, which stands for: Give Up Club Invitation.
In the original Lebensohl we have the possibility of bidding
- 3♣ showing limit hand with ♣
- 2NT transfer to 3♣.
The problem with this approach surfaces when we're dealt a hand with equal minor holdings. In this case we have to pass our partner's 3♣, risking to end up in a 4-2 ♣ fit instead of playing our 8 or 9 cards ♦ fit.
GUCI is a simple modification of Lebensohl with a solution for these situations.
We can bid only weak 3♣ or GF with ♣ suit, and partner bids either 3♣ or 3♦ over our 2NT transfer, 3♦ only when his ♦ is longer, than his ♣ suit.
Thanks to this slight alteration
- we can reach our better minor fit on the 3rd level in Lebensohl situations
- we can bid with both minors competitive weak hands after the oppenent's 1NT-2major overcall
All other parts of Lebensohl Fast or Slow are used like before.
Important warning: you have to discuss with your partner to play GUCI Fast or GUCI Slow, just like when using Lebensohl!