Yes, this is read-only. I believe it's a nice example of how you can combine different unix tools together to achieve interesting result. It's not a scalable, reliable streaming solution. But we'll get there :)
For collaboration tmate/tmux or atom+teletype are definitely better options these days.
We have used tmux session sharing in the past over Vagrant share - none of us are on the same network. But I can’t say it is seemless. Tmate.io looks like a great solution.
My team has been using Atom and Teletype to pair - but no lightweight method to share the test console. Could this be it?