[EdwardCoffin]

I think the point of the criticism I read was that the edit should have worked. There is no reason why the opaque mess following what was obviously a definition of the contents of the spreadsheet should even be there let alone be dependent on the original contents of the cells.

[jeroenhd]

The obvious reason to have other stuff depend on the value of the cell would be to store a cache alongside the formulae. In a 300MiB XSLX, you don't want to evaluate every formula every time the spreadsheet is opened.

[EdwardCoffin]

If caches have a place in a file storage format, they should at least be optional and separate from mandatory content, and I got the impression from the critique that they were neither.