He excelled in the most serious, solemn palos of Gypsy origin (often known as Cante Jondo), like Tonás, Martinetes, Soleá, and Siguiriyas, of which he recorded all or most of the traditional songs and variations. The value of his artistic legacy is controversial. On the one hand, some flamenco fans and critics consider him to be a model to imitate, an impersonation of the most authentic flamenco, and a restorer of traditional forms. On the other hand, others disregard him as excessively orthodox, academic, and cold, and regard his views on flamenco as paralysing and a threat to the future evolution of the flamenco art. They also often accused of ethnical bias, as he tended to overemphasize the quality of flamenco styles which where of Gypsy origin, while looking down to anything non-Gypsy.
It is frequently stated that some of the songs he rescued from oblivion had in fact been created by him, although he always denied it, as he believed that in flamenco there was no scope for new creations, and modern singers had to limit their work to the traditional songs inherited from the tradition. However, many of the songs he rescued are now part of the usual repertoire of flamenco artists.