Apparently it relies on a novel new "middle out" compression algorithm.

Here is the paper[1] regarding the "middle out" or "tip to tip efficiency" algorithm.

[1]http://www.scribd.com/doc/228831637/Optimal-Tip-to-Tip-Effic...

"Middle out" is not "tip-to-tip efficiency." Though they were indeed invented (discovered?) by the same team at approximately the same time, and may also be linked (depending on one's scientific, mathematical and/or philosophical definition of 'linked') they are independent algorithms solving radically different problems.

Some people have WAY too much time on their hands...