The lowest of the Brahmins might have been residing among the Vahikas, but the Vahikas were not considered Brahmins. It's fairly clear. No respectable person would mean any devout Hindu (excluding Shudras) should dwell there. So it pretty much confirms what Sparten80 suggested. Saying it was no longer considered "best practise" is trying to downplay it. It's quite clear that no respectable person should even live in that place. That is a bit more than "best practise".
The ancients said, no doubt when faced with a situation like this,
"A little knowledge is a dangerous thing,
Drink deep or drink not of the Peirian spring."
Even an eight-year old familiar with the Mahabharata, and not coming to it from Wikipedia, of all things, would catch the obvious howler in the passage quoted from the Mahabharata.
To find out why everyone who has read the Mahabharata is laughing at such a display of high scholarship, look up (in the Mahabharata, preferably, of which there are many good English translations, otherwise in Wikipedia, since it seems to agree so well)
Madri daughter of the Madras (and incidentally sister to Shalya), and
Gandhari daughter of the Gandharas.
Is it possible that Karna, born to a Suta, would have dared to speak so slightingly about the homeland of two of the most powerful royal women, one of them the Queen herself, and mother of his patron Duryodhana, the other the sister of the man standing in front of him? And are we even considering the role of the brother of Gandhari, the prince Shakuni, in the events that took place? Or would the royal family of the Kurus, the highest in the land, have accepted princesses from debased regions, as this nincompoop, a muscle-brained, fighting machine, is made to call them?
This is a late era interpolation, one of thousands that have been detected, and highlights the constant tussle for one set of Brahmins to discredit and take over the positions of others, earlier dominant.
Read the stilted language; this is no proud Aryan warrior speaking.
This was purportedly part of a battle-field squabble about precedence between the two Kings, one, Shalya, genuinely head of his ancient and noble family, the other, Karna, a fighting genius, but not from the nobility, supposedly the son of a charioteer, elevated above the heads of all by his patron Duryodhana to bind him to Duryodhana's cause for all time. And what do we get? An angry warrior asserting his equality to a noble of an ancient house? No, a quibbler droning on about the respective merits and demerits of a dhobi-list of kingdoms, some hardly heard of, obscure places of no relevance, the others among the greatest seats of power in the times in which the epic took place, rapidly losing importance in later centuries.
Even through their being inserted in the mouth of such a person, the didactic, dry-as-dust words from an anthropology-mixed-with-theology lecture that have been put in, should sound a warning: it was not an original part of the great epic poem, it was an interpolation, one of thousands detected by the very late Sanskrit used, which stands out from the rhythm and vigour of the original verses like sore thumbs.
For your further information, just to figure out what was going on, and whose interests were being served, these words so gullibly quoted were put in the mouth of the King of Anga, now approximately Bihar, but east of Magadha.
For all those who evidently fail to 'get' it, and depend on Wikipedia for their brilliant flashes of insight, Anga (and Vanga, ancient Bengal) were forbidden lands at the time of the later Vedas (Yajur Veda and Atharva Veda), at which time the incoming tribes were still grouped around the north-west, still fighting hard to survive and to find their feet; although finding mention in these later Vedas (not in the earlier), these deep eastern lands were lands "without caste". Nobody east of Gaya was considered, at one time, at the time of Baudhayan*, for instance, a very late-age commentator writing in his Dharma Sutra, to be a twice-borne Hindu, except for a handful of Brahmins, grudgingly accepted.
Four hundred years later, when the first recensions of the sung epic, the Mahabharata, were sought to be standardised, things had changed radically. By the 4th century BC, the centre of power was with the Janapadas, sixteen of them, hundreds of miles east of the bridgeheads established by the steppe-dwellers when they came to India through the passes, bridgeheads no longer held in honour but in contempt and suspicion.
Power was no longer with the old patriarchal tribes that were described by the Mahabharata, that belonged to an age long left behind. The centre of power was now Magadha; a mere hundred years later, Alexander broke into the Punjab, but couldn't motivate his last remaining Greek soldiers to cross the river to attack the Magadhan empire of the Nandas.
This was the revenge of some intriguer from the east on the previously eminent Punjabis. Wait a minute: what was that again? Ironic: as the Bengali proverb goes,
"Plus ca change, plus c'est la meme chose." We've seen this one before.
I really wish that these epics could be treated with some respect. Those who haven't even read it should stay away and not try their hand at making up history and anthropology.
* This is not Baudhayan the mathematician, before some more aspiring geniuses rush to the Internet to fill in the holes in their knowledge. The mathematician wrote a Sulba Sutra, which forms part of the Srauta Sutras, written jointly by some of the oldest mathematicians - correctly speaking, geometricians. Either he, or his namesake, wrote the Dharmasutra, which is what is being referred to here.
His dates are contemporary with the Yajur Veda, about 800 BC. The Mahabharata, according to conservative scholars, was sung and recited earlier, but was compiled only around the 4th century BC, and frozen by the late Gupta era, the 4th century AD. And that, to cite a somewhat more familiar filmic rather than epic authority, is all I have to say about that.
