That answers why a second VC might join a round. It doesn't explain how rounds work in general though. I'm not convinced we can hand-wave over the first VC join

That answers why a second VC might join a round. It doesn't explain how rounds work in general though. I'm not convinced we can hand-wave over the first VC joining. They still have criteria they're using, and they seem willing to take on a lot of long-shots. The fact that none of them picked up Lyft's latest round still says something.