For an example of comic lettering 'in extremis', look at Charles Crumb (who was the big brother of the famous underground comic artist Robert Crumb). He obsessively drew the story of Treasure Island with a particular emphasis on long conversations between how Long John Silver and Jim Hawkins. Charles Crumb clearly had some kind of psychosis, whereby the text boxes in his comics became larger and larger eventually pushing out the images altogether. The text itself became nothing more than an impression of text (Graphomania?).

Hard to find good examples... a single example at the near bottom of the page here: https://www.lambiek.net/artists/c/crumb_charles.htm

A much later example here: https://blog.mumblelard.com/post/88300090/graphomania-or-cip...

Also check out the documentary on the three Crumb brothers.