Today you're playing with John, a known Underbidder. The last time you played, you were +180, + 710 and a few other “overtrickish” scores. Is there any strategy you will use so that you will have fewer overtricks?  Tomorrow you will play with Sally, Every-hand’s-a-game-or-slam, Overbidder. The last time you played you were down 30 tricks. Is there any strategy you will use tomorrow so that you will have fewer undertricks? 

Another way of saying this: Do you change your bidding style for conservative partners, aggressive partners or down-the-middle partners?

There are two different questions and each has its answers. First, how do you get good results from these erratic partners? Second, how do you train these partners to bid down the middle?  

First we’ll talk about getting good results from John U and Sally O.

Michael Kamil: The strategy I would advocate is a very simple one. With the underbidder all close decisions must end in the more aggressive action. Thus, if it’s pass or bid, I would bid. If the choice is invite or go to game, game it is. Conversely, with the overbidder, I pass when it's close, or and I don’t raise as much with just intermediate hands. Incidentally, this strategy would include my opening bid style. I’m a  bit more aggressive with the underbidder, and more solid with the overbidder. I think it's important not to go crazy in these adjustments. At some point you would cross the line...making your own actions unsound. Basically I recommend you adjust your style slightly on close calls.

Dave Berkowitz: I would tell each one of them that I love their style and want them to maintain it. Consistency in partnership is critical. Knowing what to expect from your partner is more important than changing his style. Instead you should adapt your style to fit your particular partner, but keep theirs the same. Of course you change your bidding style. If you consider your partner a "pitcher", then you need to be a "catcher". Similarly, when partner overbids, you must rein it in. Also, it helps to know partner’s style. Many are wild overbidders when distributional, but normal bidders with balanced hands.

Marinesa Letizia: I bid very aggressively playing with the underbidder. I bid very conservatively and tend to have more solid opening bids with the overbidder.

Kit Woolsey: Playing with John U--never invite. Just go ahead and bid the game or slam myself. And accept all invitations, regardless of my hand. Be very aggressive with overcalls, and take the aggressive view when he overcalls. Also, try to convince John that I am conservative -- that might get him to be more aggressive. Playing with Sally O--reject all invitations except with the absolute maximum. If I have a hand, which is perhaps worth a game bid, just invite – Sally O will accept unless she has the worst. Also, try to convince her that I am aggressive -- that might slow her up a bit. I don't really change my bidding style much. I might be a touch more aggressive entering the auction with a conservative partner for fear that this partner will sell out too easily. Other than that I would just play my normal game.  The problem is that it is difficult to pin down exactly what "aggressive" or "conservative" means.”

Point No. 1

Enter the fray lighter with John U, but have your bids with Sally O.

Fred Hamilton: I certainly try to have a little extra for an aggressive partner. If they are quite conservative, I become more aggressive to compensate. I do not change my game much, though, because I want partner to be able to count on me.

Barry Rigal: As a pro, I find myself constantly in one of these two positions. With the underbidder I tend to assume that all bids of 2NT are forcing. When in doubt as to whether to invite, I do not always bid game – because such partners underplay the hand if THEY are going to be declarer. Playing with Sally O -- no cue-bidding -- that leads automatically to Blackwood and a slam that goes down. Take control one way or another.

Larry Cohen: As long as my partner is consistent, I am content. If I know he underbids, I'll bid a little more. If he overbids, I'll bid a little less. If he zig-zags, I'm dead. This is analogous to preempting style. Opposite a sound preempter, you respond one way; opposite an aggressive preempter you go the opposite way.

Kerry Sanborn: I don't have a rule for dealing with partners who are too much one way or the other. It is not easy to compensate for partner's tendencies, but you can know that you should accept what you deem to be close decisions. You can make second slam tries when partner is conservative. You can pull in the reins when your partner is too aggressive. It becomes something of a guessing game.

Henry Bethe: The answer is “not really.” First of all, I am more used to playing with Ernest Erratic than with Ursula Underbidder or Bernie Bidtoomuch. I prefer Ursula, as I am a great believer in plus good, minus bad. Effectively the answer is the obvious: With the chronic underbidder you accept all invitations, you bid game on invitations, etc. You expect partner to have an extra queen, and she usually provides it. With the chronic overbidder, you do not invite on marginal values, you have sounder values for your initial actions, etc. But you have to disguise this, because if it becomes too obvious, your partner will go further overboard.

Point No. 2

With overbidders you want to have your bid. With underbidders you need to be aggressive. However, you can’t be too obvious.

Billy Pollack: OK, this one I can answer. I'd say I change my style only a little. My wife tends to have her values in competitive auctions, so I take that into account, as opposed to some others, who I know I have to give lots of room to. So in those situations, yes, I change not my style as much as specific bidding decisions. With Mark Cohen, we have a rule that "Mark never has the perfect hand" -- that rule has served us well. More significantly, to keep partnerships aligned, we agree that it’s always the inviter who pushes, not the acceptor. But again, partner's conservative/aggressive style can be taken into account.

Point No. 3

Good rule. The inviter pushes, and the accepter is conservative.

To recap, playing with an overbidder, don’t show your values a second time. Partner opens 1 and you bid 2NT, which is a game-forcing spade raise. Unless you have an extra ace, don’t cuebid. With an underbidder, you have to take control more often. Bid Blackwood or Roman Key Card Blackwood instead of cuebidding. Get in more auctions.    

The second problem is how do you train partner to bid more down the middle? This is a tough problem. You can’t teach most partners. Since partner thinks he’s better than you, he won’t listen to you. But maybe partner can be trained. The experts do just the opposite of what you might think. Overbid with the overbidder, underbid with the underbidder. If he thinks you’re an overbidder, he might start underbidding.

Jeff Rubens: S. J. Simon cited some authorities as saying that one should move in partner's direction, that this would cause a helpful counter reaction; he also said that he himself found that it was sufficient merely to give the impression of doing that. I guess it matters how often you play with and against the same people (e.g., in a rubber bridge club), or whether it is a regular partner, and, in any case, how much one can influence one's partner. If partner's behavior were a given, I would take it into account and act opposite in close cases.

Bobby Wolff: I know just the strategy to use with either. The one problem is that you need to have at least two sessions with both for this to work. During the first session with John the underbidder, make sure that you underbid as much as he does, maybe more, and with no excuses. Of course, do the opposite with Sally the overbidder even if it means bidding at the eight-level. The next game you have with both, you will experience a different player, that is, if your partner doesn't plead a headache and break the date. Yes, one needs to adjust to his partner's idiosyncrasies.

Grant Baze: This was an everyday problem for me during the 15 years I played rubber bridge for a living. The solution was to underbid with the underbidders and to overbid with the overbidders. In particular, playing with overbidders, I accepted every game invitation no matter how ridiculous the acceptance. In the short run, this was expensive, but within a few months I was the only player to get reasonable results from these partners. However, that was a long-range solution. My immediate solution is to tell the underbidders that I tended to be conservative, so they need to loosen up a little, and tell the overbidders that I am a very aggressive bidder, so they better have their values in competitive and invitational sequences. As early in the session as possible, I point out to the conservative players any missed games, slams, or penalty doubles, and point out to the aggressive players any contract in which we bid too much. After that, there is no point in saying anything, except to compliment the underbidders for an aggressive action (whether it worked or not), and to compliment the overbidders for restraint (whether it worked or not). The answer to your question, however, is that I do not change my bidding style at all, but I do try to influence my partner's perception of my bidding style.

Mike Becker: I'm a believer in sharing decision making 50-50, whether I'm playing with a peer or a lesser partner, or when playing with an underbidder or an overbidder. First, I would have a chat with partner re his underbidding or overbidding, and suggest to partner that I am not going to change my game for him. I'd listen to his response and discuss with him how to proceed. Assuming I am still convinced partner will continue his ways, I'll be a Jack more aggressive than usual with an underbidder and a Jack more conservative with an overbidder, in every aspect of bidding.

These days, underbidding is anti-field. When all those tight games and slams go down, the underbidder becomes an overachiever, especially at matchpoints and/or in good fields where defenders can take their tricks. I must confess that I am regarded by others as being an underbidder, even though I don't think I am. It's in my genes. I just like to be proud of my dummy when I table it. I like partner to have confidence in my bidding. By the way, I lose at matchpoints.

Joe Kivel: I've been told that you should bid more with aggressive partners so they will get the message that they're overbidding, and do the reverse with conservative partners. In practice, I bid the same with either, although I may pass a game invite with an aggressive partner. My problem is dealing with inconsistent partners.

Zeke Jabbour: Anyone who claims that he doesn't adjust, consciously or otherwise, to his partner's incorrigible bidding style is probably not forthcoming.

1. With John, a known Underbidder:  First, I would offer him a ten-dollar reward if he would go down 1100 just once, or if the opponents were to wrap his double on us. Ten dollars doesn't mean a thing to John but it's a symbolic gesture and, from experience, I know it sends a message. I do overbid with John. It is safer than going down the middle.  It is actually instructive, as well, as he discovers that aggressive bidding is often rewarded--even when it shouldn't be.

2.  With Judy Every-hands-a-game-or-slam Overbidder (who you seem to have confused with Sally), I walk on eggs. I adjust with Judy too. On marginal hands I take a conservative view and, if she complains, I explain that history influenced my decision.  She is already aware of the occasional rewards of aggressive bidding, and lives for them. But she will slowly--ever so slowly--come to the realization that her eupeptic style affects her partner's style.

Bob Hamman: With underbidders, there is little you can do. With overbidders, really lean into it and go down a few more for a while. They are trainable. Obviously, you adjust for partner. With that in mind, if you try to do too much quarterbacking, it is a long odds proposition.

George Jacobs: Absolutely!  I am aggressive by nature, but when I play with a very aggressive partner, I feel I have to pull it in a notch.

Point No. 4

A few experts don’t worry about their partner’s style.

Chip Martel: Bidding style, slightly. Bidding decisions, perhaps a bit more than slightly.

Kathie Wei-Sender: I play the same way, I do not try to compensate.

Dan Morse: Not much change, but sometimes you take style into account.

Conclusion:

What’s important is to know partner’s style. When you have a close decision whether to continue or sign off, knowledge of partner’s style could help. What you don’t want to do is change your style and start making bad bids.