I understand about half of that :-)
It would be more efficient to charge only when needed. (sorta the reverse of what you described). Duh.
I suppose the precharge takes place before the logic is tested (precharge) and to just discharge as needed is fast. Duh again.
I wonder how much current is required for this family compared to TTL or Cmos.
This page seems to describe and compare the families.
http://www.equars.com/~marco/poli/phd/node10.html
I can follow some of it :-)