New trade group strategic alliances helped more thrifts sell their mortgage production in the secondary market last year – a development that Fannie Mae and Freddie Mac were the primary beneficiaries of – a new survey by America’s Community Bankers suggests. Overall, the ACB survey, which asked members to report on their mortgage-lending activities between Jan. 1 and Sep. 30 of last year, revealed strong growth in thrift secondary market activity. Some 72 percent