"What our research suggests is that portability isn't only determined by what industry you are in, or what particular company you work for, but it's also a result of how collaborative your job is. This suggests that workers who have already developed extensive firm-specific human capital (in the form of relationships or mastery of the firm's system and processes) should weigh the decision to change jobs carefully, because their major value is in the company they currently work for and the teammates they work with. If they do change jobs, they should make sure that the new employer is invested in their success and will give them the resources, and the time, to build the relationships that they need. (...) make sure your collaborative efforts take you outside your own team, and get you working across departments and with people outside the firm. These boundary-spanning relationships can help protect your portability—and your value in your current job."It's never to much to say it again: don't believe in «stars» but I believe in the time it takes to build a productive «star team» because performance is so dependent on the relations we build through working (making things happen) together and learning our way around with that precise team of unique persons and experiences of life.
An interview following the research by HBS professor Boris Groysberg, Lex Sant, and Robin Abrahams, based on their case study "When Stars Migrate, Do They Still Perform Like Stars?" looks at the "portability" of performance and the likelihood that some positions may improve or diminish one's prospects for career advancement: