The final effect is certainly very interesting.
There is a definite seasick effect going on here, though. Maybe I would suggest ‘flattening’ the line under the cursor so the terrain/camera doesn’t need to continually make roll/pitch adjustments. Then you could just smoothly rotate through the text without all the bobbling. The effect could be that the terrain spiral ‘raises up’ the text onto a temporary plateau as you read it, and then it falls or rises away into its original configuration as it passes your eyes.
I also find that when I run the reader at a rotation rate that is appropriate to my reading speed, is almost impossible to read because of what I suspect is the refresh rate. I’m using a 16 ms LCD monitor which is decent but may not be good enough for running the simulation at normal read or speak speed. I don’t have a CRT handy, and I don’t know the refresh rate at which you are even running the app. If your app can be configured to run in a variety of refresh rates, and/or pick the highest available refresh rates, I can try it up to 120Hz on my CRT at home, tonight.