The “classic” imagery of Rabbi Israel ben Eliezer, i.e., the Baal Shem Tob that I was always familiar with was that of a charismatic revolutionary leader who overturned the established modes of religious thought and practice. Hasidim were depicted a pietistic group reacting against the Talmudic class and instead envisioned a spirituality that was spontaneous and inherently revolutionary.
The readings as well as lectures I took years ago at the Spertus Institute for Jewish Learning and Leadership showed that for the most part this image is incorrect, and while there were “revolutionary” aspects to the rise and spread of the Hasidim (primarily connected in their understanding of Lurianic Kabbalah), the movement was grounded and embraced traditional notions of Jewish piety. Whatever innovations in meaning were given, or whatever emphasis on devekhut was promulgated, the spread of Havurot to study Mishnah and its widespread adoption in non-Hasidic circles, for example, was entirely new to me. The emphasis on spreading their influence, and ultimately control affected through communal positions (e.g. shochet) was also surprising.
What I did find revolutionary, however, was that the message (created or authentic) of the Baal Shem Tov did embody a sense that the normative modes of connection to G-d might be lacking. At least in some, the spirituality achieved for example, through Talmudic study might be ineffectual without a different understanding of prayer.
In a tale attributed to the Besht, i.e. the Baal Shem Tob, we find that he states “… the reason why supernal matters were revealed to him was not because he had studied man Talmudic tractates and Codes of Law but because of his prayer. For at all times he recited his prayers with great concentration. It was because of this that he attained an elevated state…”
While any picture of the masses of Hasidim as a throng of ignorant or simple folk is simply wrong especially in light of the printing presses and books published under Hasidic auspices, I do believe there was a sense that the spirituality once associated with the elite, though certainly not abandoned, was re-envisioned or perhaps better said refocused and reoriented with the rise of a traditionally understood rabbinic approach.
This is not to say that the rabbis were not concerned with proper intent in prayer, but that the Hasidim, at least in my understanding, envisioned a greater focus on kavannah for scholar and laymen alike in the world of prayer as well as in all areas of life.