Yet as is true throughout kabbalistic work, mussar masterpieces, and commentaries on Tanach and Talmud, the same fundamentals form a golden thread of Torah-Truth that runs through all of them.
The following is taken from Chapter 12 of the Kav Hayashar:
וְכֹה יַחְשֹׁב הָאָדָם בְּכָל יוֹם וָיוֹם בְּעֵת הִתְבּוֹדֵד, שֶׁצָּרִיךְ הָאָדָם לְהִתְבּוֹדֵד
(עַיֵּן פֶּרֶק א)
Let a man reflect day in and day out, in the time that he sets aside for introspection (eit hitboded), that he must take himself aside and rectify his sins and transgressions with all alacrity (see Chapter One).
It is absolutely essential that a person introspect (l'hitboded) well, for then perhaps a spirit of wisdom, understanding, knowledge and fear of Heaven will come upon him from On High to guide him along the straight path and keep him from straying from the ways of our Holy Torah.
If only our deeds were pure enough to merit the understanding of earlier generations, then our comprehension would be complete and we would attain whatever we desired.
Furthermore, it's clearly not something only for tzaddikim because the Kav Hayashar insists that it's a chiyuv hagadol, a great obligation (translated above as "absolutely essential"), for a person to introspect - l'hitboded - on a daily basis.
The Malbim on Hitbodedut
What Eliyahu Hanavi's Self-Imposed Isolation Teaches Us
True, the Malbim came after Chassidus and Breslov, but he himself wasn't chassidish as far as I know. Yet his commentary on these verses sound a heck of a lot like the Kav Hayashar and core Breslov philosophy.
Even if the Malbim was inspired specifically by Breslov, he wouldn't include such ideas in his commentaries unless he fully agreed with them.
Hitbodedut: It's the Torah Way
And just in the interest of full disclosure:
Do I manage a full self-scrutiny every single day?
No. I want to. I'd like to. I know I'm obligated to.
But while I manage some kind of self-scrutiny, cheshbon hanefesh, teshuvah almost every day, a more thorough self-accounting sometimes occurs only on Shabbat. Or "just" 3 times a week. Or whatever. It depends.
Yet even once a week (or once a month) is a million-billion times better than doing it just once a year or not doing it at all.
And the above gives me the chizuk to keep at it, even though I'm far from perfect about it.