So who really is a good "team player"?

Seems like everyone describes themselves as a "team player" these days. The label "not a team player" also gets thrown around a lot (and especially by people who are even less of a team player themselves). Which brings me to the topic of this post: so who really is a good "team player"?

I have experienced three types of people:

Type A: Don't have a strong opinion and don't have much to contribute to defining the project's direction, but are willing to follow your lead. This isn't terrible, and having a minority of this type on your team may even be desirable, but, let's face it, they're not that exciting to work with and you don't learn much from them. About 40% of the people I have worked with are of type A.

Type B: Have a strong opinion and a lot to contribute, but cannot compromise. This is terrible. (Let's assume here that the competing project direction is equally valid from a technical perspective.) You learn something from them, of course, but they can easily bring negative value to the team or outright destroy it. The typical course of events is

1. a meeting or a series of meetings is held in which there is vocal disagreement over the direction of the project
   
2. given that no consensus can be reached, a decision is made by the team leader or by the team majority against Type B's recommendations (sometimes Type B will pro forma "agree" so that "the team can move forward" with a tell-tale resigned look)
   
3. Type B displays one or more of the following symptoms (a) makes fun of or talks negatively about the project to outsiders, (b) defiantly hacks his/her vision into the code as fast as he/she can without discussion, (c) authors a competing paper or piece of software, (d) withholds talent, (e) becomes very quiet, (f) uses the phrase "I told you so" and delights in any trouble the project may experience in the future.
4. The team dissolves or Type B resigns (at least from the team project if not from the organization), or gets fired.
   

I have seen the above sequence at least ten times by now. If you have a Type B on the team and you get to stage 1 you will inevitably get to stage 4. Type B's comprise about another 40% of the people I've worked with.

Type C: Have a strong opinion and a lot to contribute, are willing to compromise on direction, then push as hard as they can in the direction the group has agreed upon. Yes, these are the team players. Get a group of them together and miracles happen in terms of innovation and productivity and bonding. These are only about 20% of the people I've worked with. I sure remember every one of them.