In my view unless you are doing aerobatics, side slipping, taxing, flaring or have a control failure with the ailerons the rudder should only be used to balance the aircraft not to steer it on final or at any other time. I put the thread on the instructors forum because I found some students are taught to steer all of the final leg with rudder only and to hold the wings level with the ailerons. I wanted to find out why this was being taught as I believed it to be wrong, it turned out a fair amount of instructors were doing this but none came up with a reason for it that I thought was acceptable. If you try to steer with the rudder the aircraft will skid, you will have cross controls, if you get slow you are ready for spin entry and you will be flying inefficiently. In the event of an engine failure it will reduce the distance you can glide and increase the possibility of an inadvertent spin at low level.