From a post of Shri Arunkumar Deshmukh ( I am surprised that most of this was not a part of standard training):
“I have learnt many things from Anil Biswas. In Maharashtra, it is generally found that singers neglect the words and concentrate on the taan. At one time, I too did this. But Anil taught me how to concentrate on a clear enunciation of the bol for clarity on the microphone. For many months, I studied voice modulation with Anil.
Another ability I acquired through Anil’s training is to inhale while singing without in the least interrupting the song. I worked at this until I reached the stage when it was not possible to tell when I took a breath. Yet another invaluable lesson I learnt from Anil was to avoid any change in voice, whether I was taking the highest note or the lowest. “Your voice must remain the voice of Lata Mangeshkar, no matter at which pitch you are singing,” Anil told me. This is very difficult to do.”
The post links to a nice song based on Bengali folk music in which Anil Biswas also sings