The set-up was always as the sketch when two channel systems were the norm for boat models. i.e. right (rudder) stick to the right would move the rudder to the right when the model is viewed from the rear. With the left (motor) control stick up for forward and down for reverse, with the exception of non-reversing craft e.g. i/c powered models then the spring would be removed and the stick down would be tick over, moving the stick upwards for full throttle. With a yacht again the spring would be removed, close hauled at the lower position, moving the sails out as the stick is moved up.
As Colin says nowadays, with 4 channel sets it seems to be whatever you are comfortable with, but I have always stuck with the old set-up.
