When might a Standard American bidder "bend" the five card major rule?

Question

"Five card majors" is the foundation of the Standard American system. Yet rules are made to be broken under special circumstances.

My understanding is that some bidders will adhere to "five card majors" in first and second position, but bid good four card majors (say, KQxx or better) in third and fourth position. The rationale appears to be that if your partner has already passed, you are the "captain" of the team, and the cost of misleading partner is less than if partner hadn't spoken. In this case, partner may use the Drury convention to find out if you are bidding a four or five card major.

Another variation I've heard is that "five card majors" must apply to hearts, but need not apply to spades (with or without the third and fourth seat variation referred to above). The reason is that a bid of x spades beats out a bid of x hearts, but you need to go to x+1 hearts to beat out an x spades bid. So there is a greater need of the fifth card in hearts.

Which experts or variations basically follow Standard American but allow deviations from "five card majors" under particular circumstances?

Answer 1

First, note that playing 4-card majors an opening of 1 Heart or 1 Spade is about 80% likely to be on a five card or longer suit. Thus players of a 4-card major system are already almost playing five-card majors. Bridge theorists and players for the past century have determined that even this slight difference in probability (80% vs 100% for a f+ card bid suit) is significant enough to require a significantly different tool kit for accurate bidding.

That said, there is then one simple pre-requisite for bending the always shows five or more cards rule:

1. You have no desire to ever play with this partner again, or with any opponent or kibitzer present.

The only exception to the above is when all of the above conditions are met:

• You are in 3rd seat.
• You do not have a no-trumpish hand.
• You have thoroughly discussed with partner the circumstances and hand types which make this bid, and even more importantly those which do not make this bid, and properly summarized those on your convention card.
• You are playing a Drury variant which allows responder to inquire on suit length and hand strength.

Answer 2

You basically have it right, that some people are willing open good 4-card majors with weakish hands, particularly in 3rd chair, as it is more preemptive than opening a minor, and Drury allows you to stay low. In my experience, there is no consensus on how frequently to do this in third chair.

Only once have I ever seen a player playing 5 card majors open a 4-card major in 1st or 2nd seat... and I never found out whether that was intentional. In fact, the current expert trend is toward opening 1NT with hands that are in range (a good 14 to 17) with 5332 hands... so if anything, the trend is in the other direction.

I think the basic reason for the 5332 trend is that 1NT is more frequently achieved as a contract when you open a minor or 1NT, and 1NT is frequently the best contract, especially at Matchpoints.

More frequent is to see somebody overcalling with a 4 card major, on a suit like AKxx or KQTx. Again, in such a situation, the disruptive effect can outweigh the "lie" that you are telling, although generally speaking partnerships are on the same page about whether they are willing to overcall on 4 card suits.

Answer 3

In "Bid Better, Play Better," the late Dorothy Hayden Truscott wrote, "The five card major restriction applies only to opening first and second hand bids." Ms. Truscott passed away in 2006, so the most recent 2019 edition of her book has been edited, and presumably vetted, by others.

The reason is, in third hand, you often open with "shaded" values as a semi-preemptive move against fourth hand. If you have such values opposite a passed partner, you have little fear of missing game and the difference between the fourth and fifth card in the suit doesn't mean as much. Given that you may "shade" your point count in third position, you may also shade suit length if you are making a bid that shuts out the two minor one level bids, and also indicates a good suit lead in the likely event that fourth hand becomes declarer.