[Shugart23]

Playing precision, would you open 1D with an 11 HCP hand, where shape is any 4333 ? what about any 4432 ?( the 1NT range is 13-15)

[nullve]

The Precision System of Bidding, presented by Charles H. Goren, 1971 said:

Hands with balanced suit distribution (4-3-3-3, 4-4-3-2, or 5-3-3-2 where the five-card suit is a minor) and 13-15 points are opened with 1NT. With balanced hands worth 12 points or less, it is usually wisest to let discretion be the better part of valor and pass.

Iceland won the Bermuda Bowl in 1991 doing that.

World champions Grue-Moss, on the other hand, apparently think of the (modern, more nebulous) Precision 1♦ opening as a preempt, and I posted a hand in 2017 where Grue opened 1♦ in 1st seat with

♠94
♥KJ4
♦AT982
♣J72

!!!

My own view is that if you want to be agressive, then it's probably best to follow Goren and (systemically) pass with 12 or less in 1st and 2nd seat. The reason is that if you open 1♦, partner will usually only be able to respond at the 1-level if weak. But if you pass, partner will often be able to preempt at the 2-level or higher. As a bonus you will get a better 1♦ opening, particularly because there will no longer be a strong reason to play 1♦-1M; 1N as natural. Then there will be less reason to spend 2-level openings on intermediate-strength hands just to take pressure off 1♦. And so on.

[awm]

I think in very old-school precision, the idea was to open 1NT with 13-15 balanced, pass with 12 or less balanced, and then the 1♦ opening could promise 4+ diamonds and unbalanced. However, in modern bridge everyone is opening on balanced 12s (if not 11s), and people also don't love the original precision 2♣ (could be a ratty five-card suit), so the consensus has moved towards opening 1♦ on a wider range of hands.

Assuming that you are going to open 1♦ on some balanced hands, it seems silly to do so only on balanced 12s. Most popular these days seems to be the following:

1♣ = 16+ but 17+ if balanced
1♦ = balanced 11-13 (without a 5M) or 10-15 unbalanced with primary diamonds, 10-15 with 5♣ and 3-4♦
1M = 5+ major and 10-15 (some go lighter than this)
1NT = 14-16, can have 5M
2♣ = 6+♣ and 10-15
2♦ = 4405 or move one of the other cards into diamonds; 10-15 (includes (43)15 as well as the normal three-suiters)
2M = natural weak
2NT = natural like 21-22 (some people play weak with both minors here)

Anyway, the short answer is "yes" to opening 1♦ on 11 balanced.

[bluenikki]

[quote
My own view is that if you want to be agressive, then it's probably best to follow Goren and (systemically) pass with 12 or less in 1st and 2nd seat. ]

But those "points" were not hcp. Of course for 4333 they were.

[nullve]

bluenikki said:

But those "points" were not hcp. Of course for 4333 they were.

Sorry, I meant Goren as in the quote, not as the inventor of the Goren system.