Thinking Like a Teams Player
At teams, making your contract is what counts. Bid the vulnerable games, take safety plays and don't risk the contract for an overtrick.
At teams (IMPs) your result on each board is compared with your team-mates at the other table, and the difference is converted into IMPs. Big swings matter a lot; small differences matter very little.
What this changes
Make the contract first. An overtrick is usually worth 1 IMP at most. Going down in a cold contract can cost 10 or more.
Take safety plays. Give up a possible overtrick to guard against a bad break.
Bid vulnerable games. Making a vulnerable game gains far more than going down costs, so they are worth bidding on about a 40% chance.
Bid good slams, avoid bad ones. A small slam is worth bidding when it is better than about 50%; a grand slam needs much more.
Don't fight hard for tiny part-score gains. Going down for a small edge is rarely worth it.
Example
You are in 4♥ and can see ten tricks if trumps break 3-2. One line makes an overtrick when they break 3-2 but goes down if they break 4-1. Another line gives up the overtrick but makes the contract against either break. At teams, choose the second line every time: you risk about 1 IMP to protect about 10.
Key takeaways
Making the contract matters far more than overtricks.
Bid vulnerable games and good small slams.
Use safety plays freely.