There were fast assemblers. The SC assembler on the Apple II did maybe 1,000 lines a second. The x86 assembler from Digital Research was pretty fast too. You co

There were fast assemblers. The SC assembler on the Apple II did maybe 1,000 lines a second. The x86 assembler from Digital Research was pretty fast too. You could play games with RAM disks and so forth. The thing about cross-development on a mini or mainframe that killed you was the download time. I did cross-assembly at Atari, and it was always the download time that took soooo longggg. Wrote a few smart downloaders while I was waiting for dumber ones to finish. 9600 baud sucks hard.