While I think this is very cool, I struggle to see where I would practically use this. Is the idea that you open a full screen terminal window with a very large font size in order to present?
My first thought is that it saves alot of screen switching/resizing while demoing or live coding from terminal. Fullscreen presentation until I need to show something, ^Z it into the background and run my demo or open up vim and do something, then pull it back up to where I left off without having to mess with windows or font sizes while the audience hangs on dead air. I don't know how much of a problem that is in reality though.
I've found alt-tab does the trick for me in those cases.
I don't see why not? I can easily see the appeal in creating slides in as minimal a format as Markdown. And it has a sort of geek cachet to it, depending on the audience. The only real downside I see is that you can't easily use visual aides such as graphs.