[foobar]

From reading through the old threads, it looks like a variation on Meckwell:

1♣ - 1♦ (0-7):

1♥: Either strong balanced or 4+♥, F1
.....1♠: 4+
.....1N: DN
.....2♣: No fit, not DN
.....2♦: 3-card fit
.....2♥: 4-card raise
1♠: 4+ F1
.....1N: DN
.....2♣: No fit, not DN
.....2♦: 3-card fit
.....2♥: 6+♥
.....2♠: 4-card fit
1N: Balanced, NF
2♣/2♦: 5+ unbalanced; NF
2♥: NF 5♥ + 4m
2♠: NF 5♠ + 4m
2N: Minors

This version might have trouble showing GF with 5+M and 4m, since opener will jump to 3m on the 4th round with a GF hand. Some variations use 2♥ to force 2♠ and show either GF balanced or GF canape with a 4CM.

Do folks on the forum play this method, and do you find it to be superior to the standard Meckwell treatment?

[DavidKok]

I do not play it, but have looked into it before and discussed it with PrecisionL.

Helene and I play a 'standard Meckwell treatment' which has quite a few gadgets that I'm not sure are really common. I call it Meck-not-so-lite.
On 1♣-1♦; 1M-2♣ we allow opener to ask for further information with 2♦, which can be weak (in context). The rebid scheme is straightforward, I'm only showing the 1♠ case here but 1♥ is similar. Note that we allow 1♣-1♦; 1♠-2♥ on a five card suit rather than a six card suit, so those hands are ruled out by the 2♣ bid. The range for every bid is 5-7, no need to go to a tigher range after the 2♣ bid:
1♣-1♦; 1M-2♣; 2♦-?

• 2♥: 4♥
  
• 2♠: Punt, typically 2=3=5=3, 2=3=4=4 or 2=3=3=5.
  
• 2NT: Both minors, at least 5-4 either way.
  
• 3♣: 6(+)♣.
  
• 3♦: 6(+)♦.

This 2♦ asking bid normally contains flexible hands both weak and strong, but can also we used on the strong balanced hands on 1♣-1♦; 1♥-2♣ as well as the GF 5M4(+)m hands. Responder has already denied three-card support, so us having a fifth piece rather than the promised 4 is normally not that important. This way the 3m rebids over 2♣ can be reserved for the weak canapé hands (GF hands go through 2♦).

In a similar way the bid 1♣-1♦; 1M-2♦; 2NT is a generic game forcing asking bid. Here though I would play a 3m rebid instead as a GF hand - weaker hands can sign off in the 4-3 fit in 2M. It's not that a Moysian is great, but trying to improve the partscore takes us past the point of no return. Plus, on this auction the opponents do not know what it is a Moysian, which can help a little by making their defence (or balancing decision) more difficult.

The auctions over the double negative and the 1♣-1♦; 1♥-1♠ are not as clean, and require more effort.

[PrecisionL]

Yes, I have played a version of the Cambridge Heart Complex in two partnerships for over 15 years and absolutely love it!

NOTE: 1♣ - 1♦ - 1♥ = (a) 4+♥, or (b) 2+♥ and balanced 20+ hcp is how we play.

The original Cambridge Heart Complex is 5+♥ or balanced and 19+ hcp.

Johnson-Berkowitz notes by Don Varvel was my introduction:

https://web.archive....lub/bc_jb1c.txt

Responder is allowed to rebid 2♣ or higher with 5-7 hcp.

Also, see bridgebase.com/forums/1C(Strong) for responder's rebids.

[Robertn2]

I have played Cambridge Heart Complex as part of Oliver Clarke's Precision System (OCP), as described at http://ocp.pigpen.org.uk/1c.php

The idea of showing balanced hand ranges via a 1♥ rebid is the same in Oliver's version as the one that foobar described, but the follow-ups are different. In particular, the 1♠ rebid by responder does not guarantee 4+ spades. Responder automatically makes the 1♠ rebid, even with support for hearts, with a few exceptions.

In OCP, 4441 16+ hands are opened with 2♦, so the 1♥ and 1♠ rebids by opener (after 1♣ - 1♦) usually have 5+ cards and a 4-4 spade fit can be located using Stayman if opener shows a NT hand.

My experience is that the system of NT ranges works well. The main issue I have with the overall OCP scheme is remembering which specific hands are exceptions to 1♠ for responder's rebid.

Rob