-Customizable implies minimal RUP (resembling XP) possible.  

-Robert Martin's dX method- use cases on index cards 

• Double meaning in name:

• delta X (incremental change in RUP)

• XP upside down 

-Craig Larman [ref. 1]  also proposes "lean and mean" RUP

• incorporate important XP practices 

• eliminate practices irrelevant to "agile" development