Haven't you noticed? Tamilians often refer to Padma as Bathma, Gadkari as Kathkari and Damodran as Thamotharan. That's because there is no G, B or D equivalent in the language. At least to the best of my knowledge. Ka, Pa, Tha are often used to represent Ga, Ba & Dha. There's no overt phonetic aid to clearly cue when Pa should be read as Ba, so on and so forth. I thought it's about time, we had one. The trick with introducing a new phonetic symbol is it should not upset the typography of the existing language. Keeping this in mind, I have introduced what I call, the Azhuthi Kodu or Naduazhuthi (accent line of the middle accent). Hopefully this is an elegant way of solving the problem. Or at least a starting point for tamil experts to take this to another level.