The preaching of Nitai's holy name (in the form of Nitai Vayulekhan) is directly handing over sudurlabha asadhya Krishna prema to one and everyone!
The names of Krishna's incarnations are guhya (confidential). The holy name of Sri Krishnachandra Himself is guhyataram (more confidential). And the holy name of Gauranga Mahaprabhu, which is the very deep essence of Krishna's holy names, is guhyatamam (most confidential). Krishna is Lila-Puroshottam so His name is more confidential than any other name of Godhead since it contains unlimited unique pastimes. Gauranga Nam is the personification of the prema present within those lilas, so it is the most confidential, even more so than Krishna Nam.
Yet again, even more guhya than guhyatamam is the holy name that is safely locked up in the treasurehouse of Prem Puroshottam Gauranga's heart- Nitai Nam. Nitai Nam therefore is not only confidential, it is the most confidential of the most confidential. Nitai Nam is the quintessence of all names of Godhead. It is the center of the lotus flower. Bhajahu Nitai Nam nit re!
Nitai Nam is the intoxicating elixir which one can drink incessantly, but one's thirst will still not be satisfied. If one drinks it simply once, the addiction will never wear off. So beware!
The supremacy of Bhagavan Sri Krishna and the inexhaustible glories of His Holy Name, which are now hidden even to sadhakas, will only be illuminated before the whole world by the sun of Nitai's holy name.
If one tries to speak of the glories of Krishna and Krishna Nam before the offensive-minded, irrational and foolish masses of Kaliyuga (who consist mostly of atheists or agnostics)-the only result which will be achieved is that they will increase their duskriti and heaps of aparadha by committing more offenses. This will bring inauspiciousness even to the preacher, who's own bhajan will be affected due to committing the Nam aparadha of giving the holy name to the faithless and Bhagavat vimukha jivas. In this way, the reactions of this generous attempt will only yield to opposite negative reactions. The only way to save this world from their present conditioned state is to give them the most liberal, forgiving and merciful name in the whole existence- Nitai Nam! Nitai's name not only destroys the offenses, it destroys the very tendency to commit offenses permanently from one's heart. As soon as these offenses are cleared, suddha Harinam Prabhu immediately descends from Goloka to one's heart upon Nitai's invocation. Thus, the spiritual goal of Krishna prema is effortlessly achieved. So where is the greater gain- directly giving people Krishna Nam (kare aparadhera vichaar) or aparadha bhanjana Nitai Nam (which will inevitably give them Krishna!)?