I've been looking thru older posts and came upon this thread. I am doing some work for my father-in-law who's house is wired in aluminum so I'm very interested. I devoured the CPSC report. My conclusion is that they really said,"If you don't install the purple wire nuts correctly, they may fail." I sounded to me like all the observed failures were related to improper preparation and installation. Gee, if I don't strip the insulation off of copper, just land it under a screw - I might have problems. So the CPSC declares that if I don't clean the aluminum oxide off, I might have problems. I'm going to pigtail all the outlets (carefully) and clean and noalox all the wires in the panel. When I'm finished, I'll go home and sleep better knowing he and my mother-in-law are far safer. Given their financial status, a total gut is not really an option for them.
