Spreadsheets put together two aspects: - data (raw and calculated) - presentation The original mistake is that both were made interdependent. Excel tries to fi

Spreadsheets put together two aspects: - data (raw and calculated) - presentation The original mistake is that both were made interdependent. Excel tries to fix that the hard way by introducing various reference modes, a lot of "do what I mean" magic and even nested spreadsheets/databases (aka "tables"). But it still leads to scary bugs, as the video shows: if you do things the wrong way the numbers you derive from your data are wrong and you don't even see it if you don't pay attention. While watching the video I was wondering if all those features were brilliant or insane. The answer to me is that it's insanity. If nothing else, HTML has shown for a long time already how one can - one should - make the content (data, programming) separate from the presentation. This idea has to be back-ported to spreadsheets now. The first half of the video is really just keyboard and drag'n'drop tips, while the second half is really just brutal hardcore programming: "match", "if", "lookup", references, indirections, "debug mode", ... Acknowledge that spreadsheet documents really are programs. Make a spreadsheet DSL then apply ideas from Lighttable to make it as "visual" and "easy" as possible.