How very useful!
This was the most useful post I read in ages. Not because I did not know about screen zooming, but because I knew I can zoom in the screen while holding down the ctrl key and moving the trackball up just like you were scrolling on a screen. I need to confess I was zooming in Michael Phelps' swimming pants because there was a question about what was tattooed on him. I could not find the answer, but the trackball in my mouse gave up and I could not scroll back down. So there I was with a huge arrow filling up half of my iMac's screen, and not able to scroll back to normal.
Then I went to google screen zoom on my phone and your post was the first answer I got. And what's the best in the whole thing: you were describing an alternative solution to screen zooming, just what I was looking for!!! So, again, thanks so much! I'll remember it forever.