I touch type too but the lag is very much there. Correcting a typo is difficult because unless you're perfectly counting key presses you don't know where the cursor is.
Sure, this can be an inconvenience when you type a lot and use a single-display setup. But I read way more and consider single-monitor work resemble running on crutches. This said I would probably put an eInk and a classic display alongside each other to display what I have to read on one side and what I have to edit next to it.
Messenger apps even have separate panes for displaying message threads and for editing the message you are going to submit - I could put these on separate displays (if the apps would allow moving panels around the way classic desktop apps did).
