On the topic of distance based earning for AAdvantage accounts, it seems that if you have AA flight numbers included on a non AA pnr, those will accrue as distance based instead of fare basis. I recently ticketed the following RTW itinerary. There are 2 PNRs - one for AA and one for the partners. Only the bolded flights are shown on the partner pnr, whereas the AA pnr shows everything because it was ticketed with AA.

HND-DFW-RNO / RNO-DFW-BOS / BOS-PHX-RNO / RNO-PHX-LHR / FCO-DOH-SYD / SYD-SIN / SIN-HND

My theory is that only the flights on the partner pnr will post as distance based. If this proves true, perhaps there is value for travelers who wish to optimize their AAdvantage earnings.