Organizational star performers

Interesting research covered on an HBR podcast:

• It seems to be more productive to develop star performers internally compared to hiring them from the outside. This is because outside stars leave behind them a support structure, which they need to develop at the new pace. It often takes up to 5 years for stars to become productive again. (Vlad: Hmm, I am sure one's mileage varies here, but I guess the point is that star performers are not immediately as productive at the new place as they were at the old.)
• Star performers are less likely to leave employment. In fact, the turnover of stars is half the rate of non stars
• People don't leave companies, they leave managers. If companies change management, expect some turnover
• Stars are less likely to leave if there are other stars around