This is a continuation of my theme that it is essential that your partnership have standards for bidding sequences. Each partner should be entitled to have expectations of what a bid (or pass)represents and should be entitled to rely on that expectation. It is particularly important if your treatment varies from Standard American bidding. I can live with cheap overcalls or I can live with disciplined overcalls, but I can't live without understanding what my expectation should be. If partner makes quality overcalls, I favor that, since now we will be able to do some constructive bidding. If partner makes cheap overcalls, I can live with that. Constructive bidding just went out the window and I will limit myself to "Law of Total Tricks" raises. But.... if it's one thing one time, and another thing another, we will get exactly what we deserve: bottom or low average boards.
The players who make undisciplined overcalls primarily justify them on two grounds. First, that they have some preemptive effect on responder. If the sequence is 1c/1s or 1d/2c, that may be true. Yet, too often you see the same kinds of hands that overcall 1d/1h, and bids like that have no preemptive effect at all. The other thing I hear is that it is important to get any 5 card suit on the table in case you find partner with a fit. Well, that is pretty much nonsense and can hardly justify any risk at any vulnerability. If the opponents have as much as 8 cards in their bid suit, the odds of us finding a 9 card fit in their suit is about 11%. If we don't find a a 9 card fit, it is not likely that we will be able to effectively compete. And guess what....when we don't have a fit in our overcalled suit, who has the cards and values in that suit?
In my opinion there are only two reasons to make an overcall, either you want to make a good lead directing bid or you have a suit and values to suggest a possible contract in that suit or at least competitive bidding. If the overcall is lead directing, it can only be justified if you have a suit that you want partner to lead at his first opportunity. If your suit is KJxxx or worse, what is the point of suggesting to partner that he lead the suit. Almost any other lead would be more constructive. If you don't have values or a lead directing call, what is the point of overcalling?
I think that many players do not understand that purposeless overcalls have several hidden costs. They can cost you tricks on defense, they can get you into bad doubled contracts, they tell declarer that you have at least 5 cards in that suit and that helps in getting a count on the suit and hand, they can help declarer locate key cards both in your hand as well as in partner's hand, and worst of all they give responder the opportunity to make a negative double showing both distribution and points without moving the bidding up a notch. Every time I play with my partner, Howard Christ, he says "The Pass Card is the most under used card in the box." He is not the first good player to suggest that.
If you own the blog, war stories are permitted. I was playing in a regional knockout with my pal, Rob Landham. Rob opens 1 club, my RHO bids 1 diamond. Holding AQTxxx in diamonds, I pass in tempo. Rob, bless his heart, reopens the bidding with a double and it is passed out. As we were collecting +800 and a bunch of IMPs on a meaningless hand, overcaller was getting a fast lesson from his partner on overcalls. They never survived that hand, it was all downhill from there. The partnership trust and confidence was gone and so were our opponents.
So, take my view, or create a better one of your own, but make sure your partner knows what to expect. Bridge is a partnership game, and as partners, all we have to rely on is each other.