Running a terminal inside an editor inside a terminal...

What is the use case for this that tmux/screen does not solve?

For me tmux requires too much configuration up-front. It's just not worth my time.

I spent a couple hours reading up on tmux/zsh/vim. If you want, I put my dotfiles up to save some time with configuration.

https://github.com/stickperson/dotfiles

Some more info here which might shed some light: https://news.ycombinator.com/item?id=9132352

OK that looks cool. I look forward to neovim being in my systems package manager!

You can use iterm/tmux and split windows.