System On - Conventions

This is the next instalment in my effort to document all of the basic Acol system me and Anna play.

Jacoby 2NT

After an opening bid of 1♥/1♠, partner bids 2NT with a game forcing raise.

• After a double, 2NT is still a good raise, but is only invitational.
• After an overcall, 2NT is natural. Use a cue bid for an invitational (or better) raise.
• After a 1♣/1♦ opening, 2NT is natural.

Opener then rebids as follows, supposing the suit is Hearts:

• 3♥, 3NT, 4♥ show balanced hands with 5,6 or 7 losers respectively.
• Suits at the three level show a good second suit, with 6 or fewer losers.
• Suits at the four level show are splinters, with 6 or fewer losers.

If you have a second suit and a singleton, then show the second suit first. Not sure there's anything else to say about that.

Blackwood

We play 1430 Blackwood. After 4NT and the reply:

• Cheapest bid is Queen ask. Reply with next available bid for no Queen, else show cheapest King, or just bid 6 trumps with no extra Kings.
• 5NT asks for specific Kings.

If you happen to have a useful void (not one in partner's suit), there are special responses to 4NT:

• 5NT with even number of keycards.
• 6 of the void suit with odd number of keycards, or 6 trumps if the void is above the trump suit.

The way to remember this, which sounds odd but appeals to me, is that NT is even.

We also play Exclusion Blackwood, which is a jump to the 5 level, but not in a suit that partner has bid naturally.

Finally if the opponents double or interfere after 4NT, we play 1430 as follows:

• Pass is 1 or 4, double/redouble is 0 or 3, next step is 2 without queen, next step after that 2 with queen.

Five level Bids

Think I've written this about five times, but it's never come up so I'm still a bit nervous about it:

• 5M - Asking for control in the opponent's suit, or the unbid suit. If that's not possible, 5M asks for good trumps in context.
• 5NT - pick a slam.

Michaels / Unusual 2NT

This should be fairly straightforward.

• Michaels or Unusual 2NT show two non-specific suits, and are either weak or strong. If you have a medium hand with two five card suits, then you bid twice if you can.
• In the pass out seat you only bid Michaels/Unusual 2NT with the strong version.

If there's two possible cuebids to make, as the opponents have bid two suits, then what do we do?

Fourth Suit Forcing

This is forcing to game, except at the one level (1♣-1♦; 1♥-1♠) where it is just natural. At the two level FSF asks for shape, at the three level it specifically asks for a stopper for NT.

Fit Jumps

I like fit jumps. These are the occasions we play fit jumps:

• If responder is a passed hand, then make a jump shift. For example 1♦-2♠. This shows at least four Diamonds and at least 5 Spades.
• In response to an overcall. Again this shows you have an eight card fit with opener, and shows a good five card side suit.
• In response to a weak two?

Big Hands

Just squeezing this note in here.

• Overcalls are up to 15 points.
• Double then bidding a suit shows 16-18.
• Doubling then bidding opener's suit shows 19+

To finish, a sketch of a horse (not by me!)