"It felt like the future had arrived. "
The Burroughs architecture was pretty advanced for its time, being designed directly to support a high level language and tight access security to variables. I didn't know about the upper case restriction. That sounds a bit austere, even for business use.
Edward Dijkstra wanted one when he watched it compile his program as fast as it was being read in (single pass compiler. Apparently not at ll standard at the time).