If they change this particular structure I will definitely purchased J fare outright. All AA has to do is to follow DL's scheme of counting all MQMs towards LT mileage count.

I found some J seats ex-HKG that cost $4k, with maximum BIS of 32k miles, so the EQMs will be 64k EQM. If you do LGA-HKG four times for $4k, you get roughly 72k EQMs, so not that much of difference.

Previous earning structure of EQMs seem to count directly to LT, because you fly 10k, you get 10k EQMs(eligible 100% base miles), and 10k LT miles