Clearly, ISKCON has a number of serious problems and their inability to face these problems and solve them both philosophically and practically, makes them prey to the ritvik vadis rhetoric.
All this goes to show, that there is a scarcity of knowledge of the science of Krishna, within ISKCON.
Another instruction Srila Prabhupada gave us is that the candidate for guru should be a man of flawless character, a man of unquestionable integrity, even under duress. Without sastric support, the whole ritvik philosophy collapses. No serious follower of Prabhupada would accept something that has no sastric support as a conclusive truth about the process of devotional service.
Srimad-bhagavatam 1.7.6—Hyderabad, August 18, 1976, Lecture by Srila Prabhupada:
“If one is not in awareness of the conclusion of Vedas, conclusion of the smrti, conclusion of the Puranas, and pancaratra-vidhi. Narada-pancaratra, without reference to this Vedic literature, Srila Rupa Gosvami has said utpata, simply disturbance. Simply a disturbance. Manufacturing.”
Unfortunately, this being Kali-yuga, and ISKCON having unqualified men acting as gurus, has contributed to the Utpata, and made the task of the ritvik-vadis easier, by giving them evidence that they can cite that seems to add up in favor of their erroneous doctrine. Thus, they can victimize persons week in the sastra; hence more Utpata.
 Sruti-Sastra—literally, hearing. The core Vedic literature including the four Vedas (Rg, Sama, Yajur and Atharva) and the Upanisads.
 Smrti-Sastra—A section of the Vedic scriptures including the Mahabharata and the Puranas.
 Pancaratra-vidhi—the standard Vaisnava method of temple worship taught in the Pancaratras.
Pancaratra—Vedic literatures describing the process of Deity worship.