can we ignore the neutral line connecting between the source and the load in the balanced load? justify your answers

now sure there is current flowing in the neutral line when the load is unbalanced but why ??

 

when both the source and load is wye(star) connected and balanced, then the neutrals of both the source and load are at the same potential. applying kcl at the neutral point of either source or load will result in 0 current as the sum of any 3 currents having same magnitude but differing in phase bu 120 deg always results in zero current. so we tend to ignore the line connecting the two neutrals