Raso washov, from Yehezqel 1:14, meaning 'running/going out and returning'. This concept is mentioned multiple times by R' Nahman in Liquttei Moharan, at least in 6, 13 and 79 of the first part.
(Sorry for these westernized renditions of Yehezqel's vision. They're entertaining, at least.)
While Rabenu offers fresh, original, and new hidushim on this concept from one Torah to the next, I just understood a very practical understanding of this concept that is something based mostly on what Torah 6 of L"M teaches about it.
There are times when a whole section of `avodha opens up for you. For example, you read the section of Liquttei `Esoth about speech or some other topic and it hits the spot for you. Something about it is suddenly right for you at that time, and you run with it. You begin remembering some of the key advice about it every day and it's always with you, you put the advice into action.
Then over time, something else comes up that becomes your main focus and you run with that for a while.
Someone might think this is sporadic, but it's not. This is the running out of the concept raso washov. It is natural and normal to those who have some fire in them for serving HaShem and are connected to the true Sadiq.
However, it could become problematic if there is no "washov" - "and returning". The returning is the consolidation of that which you've previously attained. The consolidation of the advice may not be near as passion filled as when you ran with it in the 'running' stage, in fact, I don't think that naturally it should be. It isn't that it is no longer essential for it, but rather, this whole process and both aspects of running and returning is an aspect of da`ath qodhesh, ruah haqodhesh, manifesting within you.
(I'm sure there weren't European style castles in the background, nor did Yehezqel wear Greco-Roman style clothing, and I seriously doubt the hayyoth haqodhesh looked so creepy - but you get the picture... I hope.)
The reason it may seem intense, firery, or sporadic is because it is - in a good way. This is the flame of `avodhath HaShem, the good inclination. When most people think of the good inclination, they usually think of something constricted, prudish, religious, proper, and goody-two-shoes. That's because of the stigma created aling with the fact that unfortunately, most people don't know anything about it and have never experienced it.
("My fire..." written in firey letters, underlined by the rest of the quote, "...will burn until the coming of the Messiah" - R' Nahman)
This phenomenon of qedhusha is something real and accessible to the sincere, to the real. The letting go, giving in to the qedhusha and going all out for serving HaShem, letting it consume you, is the breaking point of the evil inclination. It is how you smash qelipoth (otherwise, you'll just be playing patty cake with them), cleanse your soul, become righteous in HaShem's eyes, and bring closer the time of redemption and the Mashiah.
In other words, it's a must to reach this point!
The nevi'im were often considered as if crazy, as we see in the case of Sha'ul when the prophetic spirit fell upon him. In our fallen state today, this has rendered the rich crazy for the aspect of nevu'a is by high awareness of HaShem which are Torah insights, which are the source of the sous of qedhusha, they being the souls of Israel. Money and souls are rooted in the same place spiritually (this is why a man's income derives by way of his bath zugh, as do the souls of his children as well, obviously).
Therefore in a time where the full prophetic potential isn't available, the wealthy take their place, so to speak, and are driven crazy over their possessions and wealth.
What you do by nullifying yourself to HaShem and the qedhusha is tapping into your prophetic potential, ruah haqodhesh, etc, and because such a thing is akin to a fire, it is intense, sporadic, and real. "Ner, nishmath adham", you see, it just means you have a soul beyond the nefesh. You're coming into contact with your neshama when you get taken away on the joy ride of raso, running out, and you're keeping it around by shov, consolidating.
The main key to this is self seclusion, AKA hithbodeduth, finding yourself, breaking free of the dross, speaking to HaShem in this seclusion, and coupling all this with Torah, especially Rabenu Nahman's. When you get connected, in tune, set up, and tapped into the 70 Panim of Torah via Rabenu's Torah that encompasses them all, then you will see real, live-feed broadcasts from whatever aspect of Torah you learn. It all opens up and you'll see wonders. This is what Dawidh meant by "gal `einai waabitta..." (Tehillim 119:18).