~100x compression (from weird to weird.gz) is really good, no matter the input. Simple compressors like gzip are limited in what they can do. They have size-con

~100x compression (from weird to weird.gz) is really good, no matter the input. Simple compressors like gzip are limited in what they can do. They have size-constrained dictionaries, cannot have symbols of less than one bit, etc... Gzip works fine with real life data, and does it in a reasonable amount of time using a reasonable amount of memory, but it may not fare well with such a torture test. New, fancy, and really slow compressors with their contexts, arithmetic coders and neural networks will give a much better result, maybe close to ideal, but it will take orders of magnitude more time and use up GBs of memory doing so.