> (on purpose) Any evidence for this? I specifically remember one article talking about Excel's file format that was engineered in a way as to run on extremely

> (on purpose) Any evidence for this? I specifically remember one article talking about Excel's file format that was engineered in a way as to run on extremely resource-limited computers - those available when office was first released. Any complexities had to be built on top of that legacy base, and be backwards compatible. That seems to more than explain the file-format complexity, without unsubstantiated allegations of deliberate obfuscation.