It really depends on what the team structure is. Assuming it is a one day race. The team tactics are all pre-planned. If it is a strong local team, there shouldn't be a "team leader." Everyone has strengths and they need to be honest with themselves what their strengths and weaknesses are. For example, if you can't sprint, should the team lead you out for a field sprint? Of course not. As far as pre planning is concerned, if your team is dominating similar races all season, a weaker rider has to respect that and help the team get results.
A general practice is if there is a break of 4 or less, and any teammate is in it, let it ride. If the break is 6 to 10, there should be 2 from the team in it. Therfore, when you are in a break of 10 and you have no teammates in the break with you, you should do no work, and wait for a teammate to bridge. Sit at the back of the group and wait for your bridging teammate. WHen he gets close, drop back and help him get into the break. Now the numbers are in your favor and you should help drive the break.
That way, everyone knows what to expect. For instance, if you are the worst sprinter around and you get into a break of 10, if it end in a sprint and you get 10th, have you really helped your team? Great, you got 10th, but your teammate, who is the fastest sprinter in the state could have won the race.