[S.T.D.]

Aravindhan,
I too could not find any thing on Nacchinakkiniyar by google. It will be nice if you can tell us about his theory sometime.
An article by Stephan Baums and Andrew Glass (Proposal for encoding Brahmi...) has the following passage:
"Puzzlingly, the main reason for abandoning inherent [a], namely the ability to write word-final consonants or non-homorganic consonant clusters conveniently, does not apply in the case of the Bhattiprolu inscriptions since Middle Indo-Aryan has neither of these phonetic
features. This makes it likely that the dedicated long ÅmÇtrÇ, too, was first introduced in a Tamil context, and that the resulting system was only later imitated in Bhattiprolu. No such Tamil inscription has however been discovered yet."
I refer to the last sentence. Does the discovery you mentioned provide this missing link? Thanks.
Swarup