With regard to your question about Bengali style kirtana and mrdanga playing, one or two styles is best. To introduce more styles is not good. It will become an encumbrance. Who is that Krsna das Babaji who is teaching? If we introduce so much emphasis on style of kirtana, then simply imitation will go on. Devotional emotion is the main thing. If we give stress to instrument and style then attention will be diverted to the style. That will be spiritual loss. (Prabhupada letter to Satsvarupa Goswami 30th June, 1976)