For a second quarter in a row, E*Trade, Wachovia and Bank of America have the easiest-to-use online mortgage application processes, according to a study on mortgage web site customer acquisition. The Q4 report by Change Science Group Inc., Irvington, NY, says the three lenders provide easy access to rate quotes and short, trouble-free application forms. Change Science Usability Benchmarks are based on its Typifi proprietary