An improved, and for now stable, net interest margin helped lift the operating profit for Bendigo and Adelaide Bank over the second half of its financial year, and for once light up the bank's share price.The net interest margin, "after revenue share arrangements", lifted to 1.89 per cent during the June 2017 half year, up from 1.83 per cent over the December 2016 half.Richard Fennell, the bank's chief financial officer, said the "exit margin" for the period was 2.34 per cent (before revenue share arrangements) and compared with an average over the half of 2.22 per cent.This second half trend helped carry the banks full year net profit to A$430 million over the year to June 2017, a rise of three per cent from 2016.As the bank builds its capital buffers, the return on net tangible equity fell over the year to 11.6 per cent from 11.8 per cent in 2016.But once again, the second half for Bendigo excelled in comparison, with the ROTE at 11.8 per cent, up from 11.4 per cent in the first half.The Great Southern drain on resources may be abating, with loans in chronic arrears down by half to $79 million. The bank is also dealing with more bankruptcy cases as borrowers seek resolution of loans over the failed agribusiness scheme.Mike Hirst, the managing director, allowed a reflection on a cathartic period for the banking sector, one that reinforces strategic thinking on his board."You've got the convergence and concentration on cultural issues right across big business not just banking."It's an unusual thing," he said, and what mattered was "not just price. "Consumers look at other considerations, not just price these days."Narrowing his analysis to the relevance of the branch network at a time of flourishing digital channels, Hirst said: "the penalties on institutions not doing right thing become greater."What we're doing, gives you an advantage. A national footprint that proprietary to your organisation gives you much flexibility."