Thanks for the link to Pirai Vacas. Lecture was uplifting and he spoke so clearly and simply that I understood every word (He is Bolivian, so his Spanish is easier to understand than most). However, I do not think that anyone will improve their technique or knowledge of performance standards by listening to the lecture. You have the to bring those with you. Then Vacas can perhaps free up one's thinking and energies with his uplifting talk. But don't expect a shortcut to learning technique or performance standards. It is also worth noting that he plays folkloristic music (though with very high level of technique).
Yisrael van Handel
Modi'in Ilit, Israel