I try not to use sports metaphors too often; you wind up not having impact with those who are not into sports. However, indulge me here. In baseball the closer is the pitcher who comes into the game during the last inning. They are asked to finish up once the starting picture and early relief pitchers are not able to do their job. Think about it, the starter has done all the heavy lifting, and has put his/her team into good position to win. However, he/she is tired, and need someone to come in and help him/her finish the job.
A closer is not a bad idea for an article you are working on when you just can’t seem to get it done, feel at your wits end, or are just feeling “spent.” A closer can bring a bit of distanced objectivity, a fresh perspective, some new energy, and can cut out redundancies with ease.
There are several important guidelines when using a closer. First, the closer should be someone extremely happy to do the task. If you sense any ambivalence; check that out. If your potential closer is really not interested, thank him or her and move on. The whole point of a closer is to find someone who is going to enthusiastically jump in, and as they say in the South, “get er' done.” Second, give your closer clear instructions. Make it clear that your not looking for major additions and changes, but you want to make sure the article gets out the door. Of course, if your closer thinks there are significant problems with the article, this should be open for discussion. A closer really should only be given an article that is close to being done. If there is a lot of work to do, you are looking for a full-collaborator, not a closer. Lastly, make sure to discuss issues of authorship with your closer, as you would with any contributors.