[jwilliams]

> There's a reason we all use jpegs over zipped bitmaps...

It's because it's an appropriate compression - just like xz can be? Not sure what you're actually suggesting here.

[yorwba]

The suggestion is to design an application-specific format that avoids storing redundant data in the first place. When that's an option at all it gives you higher compression than any general-purpose compression algorithm can achieve.