I have, and it wasn't because they were learning to expand their powers. They were kicked out because they wouldn't accept the Khala and the Path of Ascension, and they lost control of their power. Instead of punishing the templar responsible for not destroying them, the conclave hid the problem and banished the rogue tribes from auir.
QUOTE
Although their new enlightened civilization grew and thrived, the Protoss Conclave kept a dark, shameful secret hidden from the masses. There were a few dissident Tribes who refused to embrace the Khala, believing that their individual identities would be erased to further promote the Judicator rule. The Rogue Tribes were not hostile or militant, but they believed that the Conclave’s communal agenda would be the eventual doom of their race. Thus, the knowledge of the Rogue Tribes was kept hidden, for the Conclave believed that their aberrant influence might spread throughout Protoss society and destroy all the Khas had accomplished. Convinced that the Rogue Tribes constituted a palpable threat to the new order, the Conclave ordered the Templar forces to eradicate the dissidents. The Templar, led by a young warrior named Adun, could not bring themselves to slaughter their wayward brethren. Instead, the idealistic Adun attempted to hide the Rogue Tribes away from the sight of the Conclave. Adun believed that he could convince the Rogues of the Khala’s truth by teaching them how to manipulate their own latent psionic powers. Although their powers equaled those of the mighty Templar, the Rogues still refused to submit their passionate, free spirits to the Khala. Without the discipline of the Path of Ascension, the powers of the Rogues spiraled out of control and unleashed horrible devastating storms across the fields of Aiur. The Conclave, shocked that the Templar had not destroyed the Rogue Tribes, attempted to salvage the desperate situation. If the Conclave punished Adun and the Templar for their insubordination, it would be forced to publicly admit the existence of the Rogues. Thus the Conclave decided to banish the wayward Tribes from Aiur forever. The Templar under Adun were sworn to silence as the Rogues were loaded onto an ancient, but functional Xel’Naga ship and launched into the void of space. Forever after the Rogue Tribes would be known as the Dark Templar. Over time, the legend of the Dark Templar spread across the face of Aiur, sparking the imaginations of many young Protoss. To show their disdain for the Conclave and their Judicator lackeys, the Dark Templar ceremoniously cut off their nerve-appendages, effectively severing themselves from the basic communal link that all Protoss share. It was widely rumored that since the shadow Hunters were cut off from the primal chord of their race, they were forced to draw their psionic energies from the dark, cold void of space. This tale, above all others, worked to incriminate the vagabond warriors for all time. Hunted and feared by their own brethren, the Dark Templar led a solitary existence within their space-faring vessels. Traveling throughout the cold void of space, they never abandoned their love for Aiur, and thus worked to safeguard their long lost Homeworld in any way they secretly could.