There is a player on the site who claims to be able to play bridge "one trick" better than some opponents. I don't doubt this if the opponents are say, advanced beginners.
But beyond a certain level of play, such odds become too steep even for a world class player. I'll use examples from other games where I'm sure of my premises to illustrate my question.
In chess, "queen odds" is a heavy handicap. So much so that while a beginner can be beaten by many people at those odds, even an intermediate player would be a favorite against a world champion given those odds. In golf, if an "intermediate" player has say, a +8 handicap (over 18 holes), even a world champion might be hard pressed to beat him by one stroke a hole, or a score of -10, on most days. Put another way, my definition of a solid "club" player is someone who would be a favorite with queen odds against a world class chess player or one stroke per hole odds against a world class golf player.
When I refer to "club level" competition in bridge, I mean people who play bridge regularly take lessons, and practice, and occasionally participate in tournaments against people of comparable ability, but do not play professionally.
In bridge, my understanding is that contracts are geared to a fight for the last trick. That is, when four of a major is bid, the declaring side usually has nine tricks in hand, the defending side three, and the fight is over the last trick. If partnership A is "one trick" better on average than partnership B, it would imply that the weaker partnership would lose essentially every contract that the stronger partnership A was (barely) capable of making.
Here's my alternate theory of levels: My feeling is that a club player is someone who can usually make contracts when the breaks are "normal;" e.g. there is an opposing distributions of one's trump or other key eight card suit of 3-2, (this occurs 68% of the time), or an equivalent high card distribution. An expert is someone who can often prevail against a 4-1 suit distribution, which occurs 28% of the time, or equivalent high card distribution. A world class player can beat even a 5-0 distribution the few times it comes up. So relative to the the club "68%-er," the expert player will prevail at least 20% more often (out of a possible 28%), and the world class player will win an additional 3%-5% more often. That's "less" than one trick.
So when someone claims to play bridge one trick better than others, could that possibly mean "club level" competition, or only at most against advanced beginners?