[shugart24]

Rule of 20 - HCP + length of two longest suits and can reduce to Rule of 19 if you have a quick trick

Playing precision in ACBL land , can one use Rule of 20/19 without regards to having a minimum of 11 HCP? Or is 11 HCP a minimum requirement (with an occasional exception) and Rule of 20/19 puts the thumb on the scale one way or the other on marginal hands whether to open or not ?

[DavidKok]

I think that:

• At the Basic level you'd need Average Strength, which is "rule of 19 or 10 HCP".
  
• At the Basic+ level you'd need Near-Average Strength, which is "rule of 17 or 8 HCP".
  
• At the Open and Open+ level you need Near-Average Strength in first and second seat, and can do as you please in third and fourth seat (as the openings are natural).

Whether or not you wish to make use of this full range is a different question.

[johnu]

The ACBL convention chart rules:

https://web2.acbl.or...tion-Charts.pdf

DavidKok lists the strength requirements. There are some additional requirements.

Basic chart: 1♦ must be natural or quasi natural and at least average strength.
Basic+ chart: 1♦ must be natural or quasi natural and at least average strength
Open chart: 1♦ artificial in any seat must have average strength or better
Open+ chart: 1♦ artificial in any seat must have average strength or better

Natural is 3+ diamonds. Quasi natural is a minor suit bid that is either Natural or shows a pattern that meets the definition of a Natural NT opening. Those people opening 1♦ with a void in diamonds (ie artificial) need at least average strength. Something like 4=2=1=6 distribution (10 cards in 2 suits) would also make 1♦ artificial. Does a singleton have to be an ace, king, or queen??? I think so but I've never confirmed since I don't open 1♦ with a singleton.

[shugart24]

DavidKok, on 2024-July-13, 04:06, said:

I think that:

• At the Basic level you'd need Average Strength, which is "rule of 19 or 10 HCP".
  
• At the Basic+ level you'd need Near-Average Strength, which is "rule of 17 or 8 HCP".
  
• At the Open and Open+ level you need Near-Average Strength in first and second seat, and can do as you please in third and fourth seat (as the openings are natural).

Whether or not you wish to make use of this full range is a different question.

Are you saying for Open levels, all you are required to have is 8 HCP to open, say, 1H ? (and so the response to a question by the opponents is 8-15 HCP?)

[awm]

shugart24, on 2024-July-13, 05:03, said:

Are you saying for Open levels, all you are required to have is 8 HCP to open, say, 1H ? (and so the response to a question by the opponents is 8-15 HCP?)

You and your partner should make an agreement about which hands to open. If opponents ask, you should tell them this agreement.

The Open chart deals with which agreements are allowed. Just because a particular agreement is allowed doesn't mean that it's a good agreement, nor that it's your agreement.

For natural openings at the one-level, you aren't allowed to agree to open with less than 8 hcp (or the rule of 17) in 1st/2nd position. So you could (if you like) decide to open all 8-counts with a five card major with 1M. But you don't have to make such an agreement, and you shouldn't give the opponents a range like 8-15 hcp unless you actually do open most 8-counts. I'd suggest that if you do want to open most/all 8-counts you may want to think about some of your responses and follow-ups (forcing to game on 13 isn't a great idea if partner opens most 8s, and if you up your game forcing response to 16+ you may find that the frequency is so low that a method like 2/1 GF responses isn't looking good any more).

In fact opening natural bids at the one-level with 8 hcp has been allowed by ACBL for a very long time (at least since I started playing tournaments thirty years ago and probably quite a bit longer).

[shugart24]

awm, on 2024-July-13, 06:40, said:

You and your partner should make an agreement about which hands to open. If opponents ask, you should tell them this agreement.

The Open chart deals with which agreements are allowed. Just because a particular agreement is allowed doesn't mean that it's a good agreement, nor that it's your agreement.

For natural openings at the one-level, you aren't allowed to agree to open with less than 8 hcp (or the rule of 17) in 1st/2nd position. So you could (if you like) decide to open all 8-counts with a five card major with 1M. But you don't have to make such an agreement, and you shouldn't give the opponents a range like 8-15 hcp unless you actually do open most 8-counts. I'd suggest that if you do want to open most/all 8-counts you may want to think about some of your responses and follow-ups (forcing to game on 13 isn't a great idea if partner opens most 8s, and if you up your game forcing response to 16+ you may find that the frequency is so low that a method like 2/1 GF responses isn't looking good any more).

In fact opening natural bids at the one-level with 8 hcp has been allowed by ACBL for a very long time (at least since I started playing tournaments thirty years ago and probably quite a bit longer).

As you may know, I have been teaching my son bridge for the last couple months, after about a 6 year hiatus by me. He is getting quite good and I've noticed he is tending to rely on rule of 20 quite a bit, hence opening more 9 and 10 HCP hands than when my wife and I used to play. I have used Rule of 20/19 to tip the scale when I have had a hand that I was on the fence as to whether to pass or open, especially in 3rd 4th seat. I rarely open a 9 HCP hand at the one level. I was basically wondering if there was an issue.

I would definitely be interested in any thoughts/guidance on opening 1 level bids that you (or others) might share for me to pass along to him. but otherwise, I have received the technical/legal answer at any rate

[awm]

Rule of 20 is mostly about hand evaluation; for example:

♠AQxxx ♥x ♦KJTxx ♣xx

is really a better hand than

♠AQxxx ♥Jx ♦KTx ♣Qxx

So it makes sense that if you open the latter hand (which basically everyone does), you should also open the former. I don't see this as really an agreement to open light, just an agreement to go a bit beyond counting high cards in hand evaluation.

Where people often go wrong with "rule of 20" is not paying attention to honor structure; for example without explicit agreements to open light I wouldn't open 1♠ on:

♠Axxxx ♥K ♦Jxxxx ♣Qx

[awm]

In terms of actual light opening systems, people have a range of opinions. Everything below is my own view (not necessarily expert consensus).

I haven't found opening light on balanced hands to be a huge winner; the issue is that it can help opponents to better locate values in the play and also expose you to some penalty doubles, without helping partner much in competitive sequences (balanced hands aren't great for competing). I'd prefer to keep balanced openings to a minimum of 11 or 12 points.

For unbalanced hands (and what I mean here is hands like ♠KQxxx ♥KJxx ♦xx ♣xx to give an example that I opened in a recent bidding practice with a strong club partner), I think there are definite advantages to getting in early with a call that shows your primary suit (hands like ♠KJxx ♥xx ♦KQxxx ♣xx are a bit different because we would open with a 1♦ call that isn't nearly so helpful to partner in competition). However, the issue is that there's a big difference in playing strength between this hand and ♠AKQxx ♥KQJx ♦x ♣xxx, to give another example where we would open 1♠. This is a much wider range than typical in a strong club system, closer to what "standard" bidders have to deal with.

Of course, you could require that responder just needs an extra king for each response (since opener is a king lighter) but this means you're passing on hands in the 5-8 point range where most people respond. Usually this doesn't miss a game, although it might if you have a big fit in opener's second suit, but it reduces the pressure on your opponents quite a bit and can also lead to playing inferior partials quite often. It also means you're devoting a lot of calls ("2/1 GF") to responder's 16+ point hands and lumping the very common 9-15 range into 1NT for the most part, which seems a lot worse than the "standard" 13+ and 6-12 ranges.

The approach I've taken to this is quite complex, with both a "light invite" (typically 11-12) and "heavy invite" (typically 13-14) range along with relays to handle the true game forces. One can find my methods here. In general my advice is just to give it some thought; I've seen people try just opening hands like the nine-count I gave as an example without any adjustment to partner's response methods and this often gets them to 22-point 3NTs which really have no play. That you see expert pairs doing this suggests that there are quite a lot of potential wins opening light (mostly in competition) but it really works a lot better if you have the methods to cope with the continuations.

[DavidKok]

shugart24, on 2024-July-13, 07:05, said:

I would definitely be interested in any thoughts/guidance on opening 1 level bids that you (or others) might share for me to pass along to him. but otherwise, I have received the technical/legal answer at any rate

Adam said most of it already so I'll keep it brief while basically rephrasing in my own words.

Balanced hand struggle in competition, especially if you have to pass initially (as you have no suit to bid on the second round). I prefer to put a lot of emphasis on the notrump ladder when considering opening requirements. This typically leaves not much room for opening light - using a 10-13 NT, with 14-16 in 1♦, and 17+ in 1♣, is approximately the modern approach to opening light with balanced hands in a strong club structure.
For unbalanced hands, especially with a long major suit, I think the situation is very different. While you can get in more easily with those hands later, almost always you'd have been better off striking the first blow. However, opening light (say, most unbalanced 10-counts or half of all 9-counts) puts a lot of the strain on your system. There is a case to be made that the 1M openings in Precision are overtuned and widening the range is a good idea, and without interference you can adjust well, for example with Adam's structure or Tarzan Precision. In competition though you might struggle, but that is also true if your first call was 'pass'.
I think 2♣ is too high and most Precision structures' 1♦ is too nebulous to permit a wider range without shifting the whole system a lot, and I don't see much benefit in stretching this.
Putting this all together, I think the 11-15 range is approximately right. If you wish to open most or all 10-counts you might want to change your system to accomodate this.

The conversation around ranges is complicated (and tiring) because people have very different ideas about what it means when we describe the playing strength of a hand. Going into more detail would end up being a whole essay, so I won't.

Lastly if you want to take advantage of the 1M-openings in Precision being overtuned you could also consider increasing the range at the top end, to make your 1♣ slightly less vulnerable. Especially with long hearts I think this is interesting.

[akwoo]

We've gone with opening light, but not quite as light as what Adam was talking about. I would say our minimum for first seat white is something like ♠KQJxx ♥Kxxx ♦xxx ♣x (and not with the majors reversed). We do adjust our responses - the forcing NT is something like okay 8 - bad 14 without a fit. (We're playing constructive raises, so there are weaker hands with a fit in the forcing NT.)

Yes we're guessing more than people playing tighter opening ranges, but so are the opponents.

One of these days I'll look into Adam's methods but they're probably too complicated for us.

[mycroft]

shugart24, on 2024-July-13, 05:03, said:

Are you saying for Open levels, all you are required to have is 8 HCP to open, say, 1H ? (and so the response to a question by the opponents is 8-15 HCP?)

Yes, but remember:

• They are entitled to your agreements, not "this is legal, so". If you choose to open "most 8s NV - 15", that's what you say. If it's "9s that aren't 8s", there again.
  
• Opposite a passed hand, it can be a zero count by agreement - but again, the opponents are entitled to the agreement, should they ask(*).
  
• This applies to *Natural and QN* bids - so 1♦ is only allowed in if it is "3+ or NT shape". If it "could be 1" (or zero), it has to be Average strength in 1st and 2nd, Near-Average in 3rd (and 4th). Yes, this can cause issues with hands you would have opened if you had 5 in the Major, but not if you have 5 diamonds.
  
• Oh, and 1NT still requires 10 Miltons.
  
• Oh, and 2♦, if it's the traditional "4415 minus a card" is also always minimum 10 high (can't make Ro19 with 9)), even in 3rd.

(*)Is it time to get frustrated again that this is playable totally without disclosure, I guess because "it's just bridge"? I mean, there's no place on the new or old card to discuss first or third-seat minimums (I guess there's a "description" field in the 1 bid sections); it's not Alertable no matter the strength; the opponents just have to look at you (or me) and figure they should ask, just in case, eh?

Why yes, I'm planning on playing EHAA again. We won't do this because it probably weakens the (already not incredibly strong) structure, but if we agreed that the top end of the 2 bids is 11 HCP and the bottom of the 1 bids is "any 12" rather than "12s that look like 13s", it's also "no pre-Alert, no Alert of anything but 2♣ (and the 1NT Announcement), the NSNF/2NT responses to 2 bids, and the Intermediate single-jump 3-level overcalls." Which seems - a bit much. Why do you ask?