Think about how much harder it would be if you couldn't see the inputs, code, and outputs all together at once. The difficulty you found has little to do with Excel; you were trying to learn a whole new domain by reverse-engineering a model created by an SME. Of course it took multiple days of effort to merely(!?) "understand the principles" of a brand new technical domain. Ideally the SME should be explaining those things to you as well.
> The difficulty you found has little to do with Excel;
i claim, if you allowed access to an underlying source code representation of the spreadsheet, or rather, if you made that transformation at all, you could easily add symbols and labels to transform an excel sheet into something a programmer could turn into a binary but i doubt that step inbetween is desired
I mean, the activity of analyzing an excel spreadsheet is more akin to learning where all the items in your favourite point and click adventure is and in what order to get them where, than to actually analyzing a problem
