And it simply must support overstrike since that is no longer a display problem. The simplification of the keyboard that results is amazing. I've always been

And it simply must support overstrike since that is no longer a display problem. The simplification of the keyboard that results is amazing. I've always been surprised that overstrike did not re-emerge with "bit mapped displays" and printers. I started APL on a Selectric typewriter with the dancing type ball at IBM in 1967. The sounds of that demo still resonate more than I would have ever expected. In 1975 I was using it to teach myself numeric signal processing. I think I learned it more deeply and quickly because of APL. One didn't so much code functionality as simply express what one wanted to see the consequences of. APL made exploration so easy you couldn't help it. Had IBM had any idea what to do with APL, Matlab would simply not exist.