The evaluation of lightning ElectroMagnetic (EM) fields represents the most cumbersome part of the lightning-induced voltages computation process. Their evaluation is usually performed through a numerical routine or with simplified analytical expressions, which are valid only assuming a perfectly-conducting ground or a specified channel base current waveform. This paper first briefly recalls a recently proposed analytical expression for the lightning EM fields based only on the assumption of the Transmission Line model for the current distribution along the return stroke channel. Then, attention is focused on the advantages of the proposed method in the computation of the lightning-induced voltages on an overhead distribution line in terms of computational time gain.