[edraferi]

Stockman’s sleight of hand was fairly easy to discern. In 1981, electronic spreadsheets were just coming into their own, and the kind of sophisticated modeling Stockman did was still done chiefly on mainframe computers. The output he was working with wasn’t in the now-familiar spreadsheet format; instead, the formulas appeared in one place and the results in another. You could see what you were getting. That cannot be said of electronic spreadsheets, which don’t display the formulas that govern their calculations.

This is the real double-edged sword of spreadsheets. They simultaneously surface data, logic and presentation. This enables a very fluid modelling process because you can see everything that's happening... at first. Eventually these things always become intractable hairballs, dumped on the desk of the office "Spreadsheet Mechanic" for critical repair. Ugh.

Excel's Data Tables, ODBC connectivity and named ranges help with this. It gives you have some assurance that the raw data comes from a Source Of Truth and hasn't been totally borked. Unfortunately, most users (that I have worked with) don't understand how to use these features properly, leading to a multitude of math crimes.