Thanks for this perspective. As a programmer I haven't actually thought much about how important this link between a cell in a grid and its formula may be. I

Thanks for this perspective. As a programmer I haven't actually thought much about how important this link between a cell in a grid and its formula may be. I have seen huge (i mean HUGE) Excel files full of complex formulas being built by non-programmers. Some even took whole night to recalculate. There was a programmers mindset emerging from those files - extracting common formulas to separate cells (DRY), writing 'unit' tests by using formatting (if result for sample input is less than 0 then make the cell red - which means someone broke the formula). The question arises - is there a point where a non-programmer starts thinking like a programmer, on a different level of abstraction? Is it possible to teach non-programmers some basic programming practices to make their work easier?