If Harinam is the boat to take you across the ocean of material nescience, then Nitaichand is the boatman of that boat. How will the boat move unless the boatman rows the boat? Every ship requires an expert sailor. Moreover He is the one rescuing everyone and getting them seated into the boat.
It is by Nitai’s mercy that we recieve Harinam, it is by Nitai’s mercy that we can properly chant Harinam and it is by Nitai’s mercy that we go back to Godhead by chanting Harinam. Harinam Pranam Devam!