Yeah if your analysis to takes hours to run, you should really split up the number crunching code and result analysis / visualization. Not only does it make version control of the code easier, you can save the output in an organized labeled manner (time-stamped, etc.) and, if you lose power or the kernel crashes, you don’t need to rerun the lengthy analysis if you want to make a change further down the pipeline.
It was an extreme example to drive home the point that one is "human scale time" and one is "computer scale time", people are reading far far too much into my choice of hours specifically there.
