Grant Baze advised "The 5-level belongs to the opponents." When faced with a decision on whether to bid over you opponents' 5-level contract, Grant's guidance is to "be very slow to jeopardize the possible plus position you create when you push the opponents to the five level. If the decision is close whether to push on, double them, or pass, then you should pass. If you push on and go for too much, or it is a phantom, or you double them and they make it, you have a terrible result. If you double them and beat them one, you may have gained little or nothing. If you pass, in most cases the worst that will happen to you is that you break even. This is almost analogous to a statement made by Daryl Royal: 'If the (foot)ball is in the air, only three things can happen, and two of them are bad.'"
Andrew Robson adds "11 tricks are tough to win so it is normally much easier to try for three tricks on defence than 11 on offense (ie declaring). You need an extreme feature – eg a void in the opposing suit or unexpected trump length for partner – to bid Five over Five." See Andrew Robson's article here.
If your opponents are sacrificing at the 5-level, they cannot be allowed to play in their 5-level contract undoubled. In the auction below, North's 2NT response is an artificial game forcing heart raise. North-South expect to make a heart game. East cannot be allowed to play 5♦ undoubled.
| South | West | North | East |
| 1♥ | Pass | 2NT* | 5♦ |
| Pass | Pass | ? |
So when the bidding comes around to North, the one thing North cannot do is pass. See our Forcing Pass article to learn more. The "5-level belongs to the opponents" adage advises North to prefer doubling rather than risking a 5♥ contract. North would need a very strong offensive hand to bid at the 5 or 6 level.
You can find more of Grant Baze's advice here.
