Am very sorry to ask this sir, but may i ask where have i used puranic material liberally in this thread? I have dealt with the origin of cholas from puranas, aitareya brahmana, and shatapatha brahmana here. I will agree that puranic material is not to be trusted. Fake geneologies have always been built. The Pallavas give their earliest ancestor as Ashokavarman and yet claimed descent from Dronacharya. This shows that such kings / men were just ordinary men, who upon coming to positions of power, took on a brahmanical status to go with it.
And if I am not wrong, you yourself have said that sanskrit prasastis earned mythical ancestry for aspiring royalty. Hence the Puranic pronouncements
could merely be to corroborate such mythical lineages, and hence interpolations. Your liberal use of Puranic material lowers the standard of your posts imho.
The Aitareya Brahmana states that Vishvamitra had a hundred sons, but that when he adopted his nephew Sunahsephas he proposed to make him the eldest of his sons. Fifty of them assented, and them Vishvamitra blessed that they should "abound in cattle and sons;" the other and elder fifty dissented, and them he cursed "that their progeny should possess the furthest ends (of the country)," and from them have descended many of the border tribes and most of the Dasyus.
The above is one translation of the relevant portion of the Aitareya Brahmana. From whatever comments I have seen now (thanks to google) it looks to me as though the general opinion of scholars is that this Viswamitra story has been placed in Aitareya Brahmana (which belongs to the early period of scriptures) when the vedic people (Aryans) were slowly spreading east and had begun to come into contact with the different indigenous people (tribes?) ; the story is also interpreted to mean a disparagement of Kshatriya by brahmanic elements. Below are extracts from "Indian Caste" by John Wilson (downloadable from URL
http://ia600406.us.archive.org/35/items/indiancaste00unkngoog/indiancaste00unkngoog.djvu).
"ORIGIN OF CASTE--NOTICES IN THE BRAHMANAS. 155
The pre-eminence of the Brahman to the Kshatriya is
here set forth by the alleged greater acceptability to the
gods as a sacrifice of a Brahman than a Kshatriya ; and
by the adoption of the Brahman, (said to have been set
apart for sacrifice) by Vishvamitra, A Brahmanical
disparagement of Vishvamitra and his consociates is also,
intended by the absurd allegation that the aboriginal
tribes of the Andhras, Pundras, Shabaras, Pulindas, and
Mutibas were descended from them*. These tribes
belonging principally to the South of India, appear from
the notice taken of them, to have been known to the
Aryas at the time of the composition of the Aitareya
Brahmana, while they were not as yet gained over to
Brahmanism. The Andhras were the inhabitants of the
province which was afterwards denominated Telingana ;
the Pundras are supposed to have occupied the Western
Provinces of Bengal ; the Shabaras are placed by Ptol-
emy near the (mouths of the) Ganges; and the Pulindas
are located by Ptolemy along the banks of the Narmada
to the frontiers of Larice, but in the Indian literature
they occur in different positions from the Indus to the
South."
Hence, the immediate conclusion that just because Aitareya Brahmana sets out a certain mythological story and the story makes Viswamitra curse his first fifty sons (elder to madhucchanda) "Your progeny(descendants) will all become Chandalas." And it is the Brahmana text writer's annotation that "they thus became the Andhras, Pulindas, Sabaras, Mutibas, Paundras, and dasyus."
I give below the original from the Brahmana itself so that there need not be any further doubts:—
तस्य ह विश्वामित्रस्यैकशतं पुत्रम् आसुः पञ्चाशदॆव ज्यायाँसो मधुच्छन्दसः पञ्चाशद्कनीयांसः ।
तद्धॆ ज्यायाँसो न तॆ कुशलम् मॆ निरे ताननुव्याजहारान्तान् वः प्रजा भक्षीष्टॆति त एतेऽन्ध्राः, पुण्ड्राः, शबराः, पुळिन्दाः, मुतिबाः इत्युदन्त्या बहवो वैश्वामित्रा दस्यूनां भूयिष्ठाः।
Please note that the exact word used is "andhraah" and not "aandhraah", the rest four are tribes or castes in later times and Sabaras are found in different parts of India. Mutibas are not known subsequently. "udantyaa" will mean the end-most; here it can be taken to mean the lowest of dasyus, or living at the very edge of (the Aryan country). If we take the latter sense of the word, it may simply mean that Viswamitra cursed his sons to the farthest edges of the Arya country.
In any case there seems to be no case to conclude that Andhras are Viswamitras and so "The cholas themselves were brahmanical vishwamitras from the puranic view." etc. Once Viswamitra the father himself pronounced them to be "dasyus", there is no rational basis to consider Andhras, Cholas or anyone else (Sabaras, Pulindas, etc.) as "brahmanical viswamitras" whatever the meaning you deem to assign to this usage.
It is also difficult to imagine that the entire Andhra country was unpopulated till the cursed sons of Viswamitra landed there and started populating it. And since the other four categories Pulindas, Sabaras, Mutibas and Pundras did not have any region of their own, but have at best been recognised as tribes or certain groups of people, there is enough justification to propose that the andhraas of Aitareya Braahmana were just another existing tribe and Viswamitra's cursed sons mingled and merged with these tribes. But whether these andhraas are/were the people of Andhra in historical times, again, will require further deep study.
Before closing, I will request you not to form quick conclusions regarding such abstruse topics on the impression that some remarks in our scriptures can have only one meaning which strikes you and no other interpretation. Most of our scriptures are vague in so far as their historical contents are concerned. It will be necessary to check and cross-check and re-check before forming any conclusion imho.