A plateau in the level of profit across the top tier of the Australian banking sector is producing one consensus among rivals and followers: the industry had best sharpen up on costs, among other levers.Whatever works, the shareholder subset of the stakeholder class will be looking for a more apt metaphor, maybe warm drafts that shift and lift industry returns in the manner that renews dividend growth and maybe total shareholder returns.Major banks "are seeking to more assertively reduce costs, strategically rebalance portfolios and consider their long-term strategies for low growth,lower margin and capital intensive businesses," KPMG said in an analysis of the half year of major banks profits.It's an echo of the year passed."They are very good at adapting in these circumstances," Andrew Yates, a financial services partner, said yesterday."There's a focus on fixed costs … certainly the trajectory for returns is up."Commonwealth Bank produced an ROE, cash basis, in the latest half (for them, ending three months ago) of 16 per cent, two percentage points clear of the sector average.