[alecco]

  > If you look at some of the stats people are posting, it's the
  > compression that takes the most time, not the decompression

5 vs. 11 seconds. Worse than 2x slower decompression:

http://news.ycombinator.com/item?id=1458697

If you have to wait minutes to download the files it doesn't matter, but if you already have the file locally it is very annoying.

Also if this is used extensively on projects with a large server deployment this matters even more related to latency and energy consumption. That's why Google has their own compression algorithms derived from BMDiff and LZW (Zippy.) Think about it. Speed matters.