I've been wondering if I'm overthinking it, so it's nice to hear someone suggest that. For what it's worth, we don't know of any bugs when creating new versions of A; however we're working with data collected from an instrument and as we learn new ways to calibrate the data, the pipeline code that creates A changes as well. In practice, updating the calibration is just like fixing bugs but I suppose it feels different because the reason is due to our lack of understanding instead of QA failures.

@JonasH I'd say they are reasonably optimized. I used 1h in the description of the problem to simplify the problem, but really E-->F (the longest runtime of the pipelines) takes several hours. That script is written in FORTRAN and I believe it's fairly optimized. I certainly know the type of scientists that write highly unoptimized code..

I appreciate the feedback! Yes, I used non-descriptive names for the sake of the example but your assertion at the end is particularly useful. I think my code is more readable already.