Duryodhana wanted to discover a way to cheat Krsna, and that is why he told this. Dharmic, or religious persons, do not tell lies. They serve their father and mother. They do some chanting to Krsna also, but for their personal benefit. This is also somewhat anukula (favorable) to bhakti. It is not pratikula (unfavorable).
Let us consider Sanaka, Sanandana, Sanatana, and Sanat Kumara (the four Kumara brothers). They are rsis, or saints. Their activities are favorable to Krsna, but not as favorable as those of Brahma. Brahma is more favorable, but not as favorable as Sankara. Sankara can perform very heartfelt, intimate services to Krsna. He can obey whatever Krsna orders him to do, but Brahma cannot. That is why it was Sankara who Krsna told to preach Mayavada philosophy. No one else was qualified to do this duty, so he is more favorable. Dhruva is also favorable, but not like Prahlada Maharaja. Prahlada Maharaja has no worldly desires. He wants only that all creatures, all souls, go back to Godhead, and he is willing to taste Hell and all suffering for others' welfare. He is favorable to Krsna, but Hanuman is more favorable than Prahlada. Hanuman serves Rama in every way, but he is not as favorable as Laksmana. Laksmana can sit on the same throne with Rama, but Hanuman cannot. Still, Sita is more favorable (anukulyena krsnanusilanam) than Laksmana.
It is essential for us to understand all these things. Draupadi is more favorable than Sita. Sita is favorable to Rama, but Rama is a plenary expansion of Krsna whereas Draupadi is serving Krsna personally, as is Arjuna and the other Pandavas. Still, Uddhava is more favorable than the five Pandavas and Draupadi. Do you know how? He is Krsna's advisor, brother, servant, guru, and His all-in-all. Krsna could not send the Pandavas to Vraja to speak with the gopis, because the Pandavas would not be able to understand them, so He sent Uddhava.
Uddhava is the most favorable within the whole of Dvaraka and Mathura, but he is not qualified to be the dust of the gopis' lotus feet. Every gopi is more favorable than Uddhava. What to speak of the gopis, Yasoda is much more favorable to Krsna – many millions of times more favorable than Uddhava. What to speak of Yasoda, a peacock of Vrndavana, a cuckoo of Vrndavana, and a parrot of Vrndavana are more favorable than Uddhava. Uddhava is not qualified to be even the dust of Vrndavana.
Vrndavana: November, 1994