> they definitely didn't write only pseudocode that wasn't runnable (to see the results) for months/years.

GT started students that way and it worked well for years. A full semester (number varied, but was the CS 101 course, 1301/1311/1501 or something like that), taught with only pseudocode. They got rid of it because of appearances, trying to be like every other school out there. Eventually settling on Python, I think, after a brief stint with Scheme (which ended after a major cheating scandal).