That is true about making small adjusments rather than big ones. If I remember correctly, the last time it flew straight without engine power the rudder trim was pretty much in line with the fixed vertical stabilizer (leading part of the rudder). I had several people look at the plane (to make sure I'm not seeing things) to see if the whole rudder is in a straight line with the fuselage airframe and all agreed with me. Just have to make the change and fly again.