I frequently have worked with people in Bob Langer's lab, which is an absolutely enormous group. Most of them described it as being a place where virtually any

I frequently have worked with people in Bob Langer's lab, which is an absolutely enormous group. Most of them described it as being a place where virtually any piece of equipment you wanted to use was available to you, but you will have very little supervision. For a scientist who has a crazy idea that doesn't want to be micromanaged, that can be an ideal environment. Those crazy ideas are the most likely to be published in Science or Nature if they work, in which case, having a famous PI like Langer or Church helps a surprising amount. So, yes, being in a huge lab is a bit of a pyramid scheme, and probably gives undue credit to the PIs. But, for the right person, it can be the perfect environment to test your ideas and, with a bit of luck, publish some high profile papers.