Collaborators will often meet at conferences or similar, and then go out of their way to attend the same conferences. There's a big difference between the fast

Collaborators will often meet at conferences or similar, and then go out of their way to attend the same conferences. There's a big difference between the fast in person work that lays the ground work, and the refinement that goes into finishing the paper. The internet is way more useful for the latter, imho. It's much easier to share ideas quickly on a black board...