Article: Use your star as a catalyst for productivity by amplifying the halo effect

Adding a star developer or architect—from here on we’ll just call them a “star”—to the team does more than improve your organization’s productivity by the amount that star can do. A halo effect often occurs where the existing developers on your team begin to improve their effectiveness too. This halo effect can be either amplified so that nearly every person on the team becomes better, or it can be isolated so that few, if any, people are affected by it.

http://www.techrepublic.com/article/use-your-star-as-a-catalyst-for-productivity-by-amplifying-the-halo-effect/