We need to ensure that the pendelum does not swing too far the other way. As the article points out, superstars will often shine regardless of how they are managed and failure to bring the next group of people along creates single points of failure within an organisation. An approach I have deployed (it takes planning and clear goal seeting)is pairing the two of them together - your superstar moves into a mentoring role and they help bring your subsequent tiers along with them. You have shone the light on your your superstar by engaging them in the process and have increased your bench strength.