I suppose it won't lag the way a low-bandwidth serial port would lag (letters and edits coming visibly late) but much like mosh "lags" shell output (i.e. network lags are just swallowed and the newer packets will update everything once they arrive, and you can keep on typing).

So you could type as fast as you can, the computer would update its front buffer without delay, and all keyboard commands to move around in the editor would be executed instantly just like normal but the screen would only get full updates five times a second.

I could work with that.

Sounds faster then the mechanical tty's I started out on..

Yes, that's horrible.

That's in black and white mode, not grayscale too, which I'm sure is going to be even slower.

I regularly VPN into work from my home and experience 200ms+ delays quite frequently. In my experience, that delay in updating the screen to reflect my typing is not particularly problematic.

Not good for coding. But check documentation on the side? Maybe.