Computers then were like computers now... It's one thing to get python to spit out an answer to your problem, but it's quite a bit harder to be sure it's spitting out the right answer.

If I was the supervisor in the above situation, I wouldn't let them cut those corners, since it's far more important to get the right answer when $2B of project could be led down totally the wrong path if a calculation tells you you need 10x less/more uranium than reality because someone shuffled up some punch cards wrong...