I think that in a sense what is said about Lacan is true for more philosopher-psychologists. It is definitely true for Nietzsche. Not because he is so complex - he is not, rather straightfoward and unwavering - but because he speaks to a certain constitution, precisely as you clarify at the end of your OP on Difference & Repetition. One can not understand Nietzsche if one demands, a priori to any investigation, that all conception of existence must be identity-based. Existence must be flux-based, illusion/fantasy must be the interface, otherwise it’s not just impossible, but unbearably boring.
I would like to participate in that thread, but feel it is folly do do so without having the Deleuze background. I might look into the sources you suggest, or I might go through with reading the book itself, at least part of it. In any case I’m very interested in the angle you take on it.
As to the ceiling: I find myself gradually elevating that ceiling every time I revisit a philosopher. Like with Zizek - I notice that I understand more of what he’s implying now than three or four years ago when I started reading him. I now understand much more of what is meant by fantasy and the phantasmatic. As simple as it may seem, or be even, I suppose I lacked the experience to truly fathom the role fantasy plays in the activity of causing the world to make sense. Fantasy is the ground to most value-assessment, to be sure, even to accepting the value things such as food have for us - the difference between the tasty meal we perceive vis a vis “the slime we actually eat”, so to speak.
Speaking of French, here too fantasy plays a fundamental part. What of the suggestions caused by the visceral reality of a language? In effect, can we not compare a language that we do not speak or understand at all to the Lacanian Real? And in the first instance, it is fantasy which allows us to connect to that language at all - we must firstly imagine that we understand, imagine an order, project our need of identity into the form-less stream of sound – not sure if I am making sense. Perhaps it is a different kind of fantasy that connects me to the French language - perhaps even the opposite of it being the Real - in fact I sometimes feel that French is, to me, the real (truly viable) symbolic order, pertaining to/disclosing reality in a way that actually allows me to exist as a ‘perfect’ (fully self-valuing) entity. A language translates the subject to himself, and all languages do this differently, producing different subjects and different hierarchies of degrees to which subjects are disclosed to themselves.
We can only be disclosed to ourselves in ways that we can accept - value. If we are disclosed in a way that we can not value, we necessarily destroy our existence. That is to say, we either withdraw from the appearance, becoming deliberately blind, receding into the dark, or we impose violence on ourselves in order to no longer resemble that which has been disclosed. So in this sense, psychoanalysis is not the art of disclosing the subject as he is (directly mediating the Real into the Symbolic Order) but as he can accept himself. It is probing the fantasy realm belonging to that particular subject for pathways for the Real to stream into the Symbolic Order. A subjects idea of himself is always structurally phantasmatic. In this aethir-like substance, the subjects decision making capacity is suspended like a spider in a web, he walks the fine threads he has woven to devour the Real as it has been trapped in his fantasy in order to sustain - ahh, okay enough, or too much!