Raganuga is not "Rasa Sadhana"

Raganuga is not "Rasa Sadhana". Srila Bhaktivinoda Thakura explains the difference in Sri Caitanya Siksamrta, Chapter 7, Part 1

"Those who have not attained pure rati and sense control make futile attempts to become qualified for rasa by practicing rasa. That taste which arises naturally in a person on the level of prema is called rasa. The discussion of rasa is only a description of how the various elements combine in the different rasas; it is not a part of sadhana. Therefore, if anyone says that he will teach you the sadhana of rasa, he is an impostor or a fool."

Some devotees have used the last sentence in this quote as a reason to denigrate any book or instruction about the science of raganuga bhakti as outlined in the sastra. But if we look at the whole paragraph, we see that the point is that raganuga is not rasa- there is no "rasa sadhana"- sadhana means the practice stage. Sadhya is perfection, and only a person at prema experiences rasa, as explained above. But certainly a practicing devotee can have ATTRACTION to a particular rasa- he has desire for that rasa with Krsna and wants to develop it. Then he may embark on the path of raganuga sadhana, focusing wholly and solely on that aspect of loving relationship with Krsna.
This can certainly be taught- in fact one needs guidance to do so, both from a guru and the sastra:

When both kinds of devotees, the one yearning for ancient lobha, the other for modern lobha, hear how to acquire the devotional mellows possessed by Krsna's eternal associates, or nitya parikara, they seek guidance from the proper scriptures. This is because the authorized method for attaining bhava is delineated in scriptural injunctions and purports; no other sources for receiving this information are indicated anywhere.
The following analogy illustrates this point: A person becomes greedy for milk and its products, but first he must want to know how to procure milk. He then has to seek advice from a trustworthy person conversant with the subject who will tell him how to purchase a cow and how to take care of her properly. In other words, knowledge on a subject cannot be simply invented-proper guidance is necessary. RVC

So after developing a desire for a certain rasa with Krsna, one should definitely cultivate that desire or greed, by using the sastra or the guru's guidance. But if the sastra is not referred to, and there are many misconceptions about raganuga, then how can we follow this instruction from our acarya Srila Visvanatha Cakravarti Thakura?

This book was written for this purpose- to present the guidance from the sastra, and parampara, without error, speculation or popular opinion. It has been thoroughly researched, as is clear from the text, which is thoroughly referenced. Please send or pass it on, especially to those who consider themselves leaders or gurus or even those who give bhagavatam classes in the morning, temple presidents and so on.