[blackshoe]

You play a "two card" system which is basically 2/1 when vul (at MPs) or when not at favorable (IMPs), and basically Precision when not vul (MPs) or at favorable (IMPs). In an effort to keep differences between the two cards to a minimum (and to make best use of the bidding space) you have the following agreements regarding opening bids:

2♦ shows a balanced 21-22 HCP (about 80% of the time), an unbalanced GF with primary diamonds (about 15% or more), or a balanced 27-28 HCP (less than 5%). This bid is used on both cards.
2♥ shows a "Precision 2♦" opening on the "Precision" card: 3=4=1=5, 4=3=1=5, 4=4=1=4, or 4=4=0=5, 11-16 HCP; it shows a normal weak two in hearts on the "2/1" card.
2NT shows a "bad" three level preempt in one of the minors (on both cards) so that the three level suit opening shows a hand which, basically, partner would be happy to see when he bids 3NT to play.
4NT shows a "good" five level preempt in one of the minors (on both cards) so that partner may be better able to evaluate slam chances.

Here's the problem: the latter three openings are Mid-chart. The 2NT bid requires six board segments, the other two require two board segments. How would you modify the system if you can't find a venue where the Mid-chart is allowed?

My thoughts:

I included the 2♦ bid because I think it's important (it helps when you have a minor-oriented GF, for one thing) to keep it, if we can.
The 4NT opening is very rare, so could probably be dropped without much loss.
2NT as a transfer to clubs showing a weak preempt in that suit was suggested to me, but that's also Mid-chart, so it doesn't help. I suppose we could use it as two suited in the minors and weak.
The "Precision 2♦" hand type needs a way to show it, but if we can only use 2♦ for it, what do we do about our strong 2♦ opening, which we'd really like to keep? This one may be the system killer if we can't find a way around it, and I frankly don't see one.

[lalldonn]

You can open 1♦ on those hands with the singleton diamond, and even 4405. It's not something I have ever done or would want to do but I know some do it. I think awm knows more about such systems than most people here.

[brian_m]

blackshoe, on 2012-April-14, 13:23, said:

<...>
The "Precision 2♦" hand type needs a way to show it, but if we can only use 2♦ for it, what do we do about our strong 2♦ opening, which we'd really like to keep? This one may be the system killer if we can't find a way around it, and I frankly don't see one.

I echo lalldonn's advice. It's more than 20 years since I felt the need to dedicate a bid to the Precision 2♦ opener. The sky's not going to fall in if you open 1♦ on 4414 shape, and if the idea of opening 1♦ on a void is too much for you, then put the 4405 shapes into your 2♣ opener.

I find it useful to be able to make a 1♥ or 1♠ response to 1♦ mandatory on any hand holding a 4 card major, 0-10 HCP and NOT forcing, with 2♣ and 2♦ as conventional invites, but AFAIR this part of the system (general licence - now known as level 3 - in the UK, or it used to be) was one of the many things which I found violated the GCC when I moved across the pond.