I think the problematics of this discussion should be narrowed down. “Traditionalism” is more like a retrospective term (those people are grouped under "traditionalism" banner, but they didn’t apply this label to themselves collectively). If a current of thought is meant, then it’s just the "declaration" of the certain waymarks. And they are based on something, bearing a foundational value.
This "something" was the data, which those people came across. It appears that they didn't unearth it in publicly available books back in the day. They studied the documents treasured by the esoteric circles (in which they were admitted) under the guidance of respective tutors. For example, this goes to Fristhjof Schuon, who was initiated into the Sufi Shadhili order, and Titus Burchhardt (into the Darqavi Order). And, of course, Guenon (was initiated into a number of esoteric groups). That type of structured, complex and disciplined presentation (with a precisely defined terminology) on esotericism, which is found in some of his writings, can’t appear out of nowhere. There must have been supervising figures behind his literary work. And it seems that they acted on the basis of the guide-lines, rooted in the long-standing, knowledgeable outlook (which includes the notions of the Noetic faculty and its central role in the Higher mysteries, Supreme Identity, the contrast between Initiatic and Mystical states, Initiatic transmittance etc.). Guenon was a vessel, conveying what someone else imparted to him. He said so himself that there were some esoteric sources, some initiation experts behind him.
It can be seen from the tractates by those authors that the general scheme of the world happenings, present therein, has a lot in common with what can be found in Steiner and in the books like “the Transcendental universe” by Harrison. The Christ principle is also recognised there.
The difference lies in the certain subtleties, which put a new complexion on the matter. One of them is the concept of “Infinity” as the ultimate source of everything. Guenon elaborates on it in his “Multiple states of Being" book. What he develops there is close to the principal considerations in Jewish Kabbalah (which he listed among genuine initiatic traditions), i.e. a distinction made between “Ein Sof" (“infinite”, “with no end”; “concealed God”) and “God of manifestation”. This corresponds to the delicate interrelation between Infinity and Unity (also, Multiplicity arising from the latter), posited in the said book. He gives an outlet for understanding Infinity (of course, as far as a limited earthly mind is capable of getting a grasp of such lofty reality, never fully comprehensible) from several viewpoints. Among those are universal possibility, absolute knowledge and some others. And he proceeds with describing the succession and the interaction of the metaphysical principles (organically implicit within one another; Infinity being the supreme one), which together constitute "metaphysical order”. Some of Steiner’s lectures offered a glimpse into how humans felt “qualitatively” about Numbers in the past. Steiner started with “One”. Guenon starts with “Zero”. It means “Possibility of Manifestation” inherent in the global Possibility-substrate within Infinity (“possibility of non-manifestation” is also present "there"), as long as it is not yet affirmed/differentiated (manifested) and tends towards “the mold”, which would reveal what is implicit in it, which would fashion something out of it. Unity ("One") is THAT "mold". Therefore, "One" is the affirmation of "Zero". Unity is also an expression of "non-manifestation possibility", since, being the principle of all manifestation (Multiplicity of beings and forms in “Nature”), it’s not manifest in “Nature” itself.
Actually, there is something akin to what you called “mastering the language of creation” in this supposedly "old-school" view on esoterics. Someone, who successfully integrates (Involution) the fruits of his journey in the manifest states on the summit of Identity with the Highest and the Unconditioned, becomes an immutable foundation for the corresponding possibilities being actuated. This is a "bliss of tranquility, which is full of activity” (not action, though; the state of overflowing with energy is meant, in which one emanates and remains unhindered, not subject to change) described in some Taoist texts.
The opposition between intellect and spirit is a tricky issue in this case. It is applicable to Guenon’s situation, only if we assume that he stayed on the ground of discursive intellectuality his entire life. However, he dropped a few indications here and there that he actually experienced some of the alleged “initiatic states” (which are to be viewed as supra-rational). He stressed that they were reachable by activating the special power of intellectual transparency (“Intellectual” in a higher sense) with the seat in the “subtle Heart”. He observed on another occasion that the exercises, performed in “Hysichasm” (the mystical path in the Eastern Orthodox Christianity), had likely distant "high initiatic" origins. However, in the case of orthodox monks they degenerated into mysticism (they practise so-called “Prayer of the heart” there; the emotive aspect of the doing is accentuated).
I suspect that the answer to this question (is it necessary to have exact super-sensible perceptions in order to talk about the spirit at all?) is conditional upon an exhaustive survey of the "corporate dynamics” in the Mysteries. And it should be retraced back to the times when the Earth with all its kingdoms was represented with a different kind of "material" phenomenality and a picture clairvoyance was routinous for (what then was) humanity. That faces some obstacles, obviously. Guenon gave a hint that a human’s natural proclivity (while being tied to the form of “dense” embodiment, currently known to us as "material human body") for activating that Supra-rational/Noetic mode of knowing was dependent on the peculiarities of his preceding physical existences. Guenon didn’t deny the soul’s sojourn in various kinds of physicality; he was convinced, however, that each kind is fully experienced only once (that’s why he didn’t believe in reincarnation). It is if some human entities somehow enjoyed the capability (during those very distant epochs like Lemurian) for "divining" the high metaphysical principality behind concrete phenomena and learning to orientate towards it, while others didn’t. That served as a precondition for this later division into the Greater mysteries (High Initiates with talents for the Noetic knowing) and the lesser Mysteries (Initiates with a disposition for clairvoyance).
Perhaps, an important requirement for establishing congruity between Anthroposophy and "traditionalism" is making it clear if “Intuition” meant the same both in Steiner and Guenon (who said The Noetic intelligence was "Intuitive") cases or not. Strictly speaking, Intuition in Steiner's sense indicated the capacity to "live into" the very Egos of spiritual Individualities. Traditionalist’s "Intuition" is about going beyond Individualities. So, it’s not exactly the same. Probably, the actual implications of Steiner’s "Intuition" were wider than what he mentioned to others when using the term. I dunno
That sentence “To Steiner Initiation was about..” is a bad choice of words. What I mean is that the techniques of making precise distinction between spiritual individualities (this is, of course, impossible without developing exact seership) were highlighted by RS as indispensable for mastering “Initiation-science” (in his sense of the word). High Initiation in the "traditional" sense was about something different.
I get it that you doubt the tenacity of the whole thing, because you made the certain impression with Guenon. But if one goes into this paradigm with both eyes open (reading and understanding a sufficient amount), it becomes a little more difficult to write it all off as insignificant and/or erroneous, right away. Admittedly, I don’t understand everything (I haven’t studied even a half of the available material yet, which includes books, articles, letters). Further inquiry (involving a comparative study of spiritual streams) might help. I’ll let know if I find anything decisive.
P.S. To be honest, the reason I read books and live with questions isn’t my love for theorising. This is an exercise of seeking for the objectivity of Truth and overcoming the soul’s tendency to put wishful thinking on a pedestal. It is a way of purifying one’s "astrality", essentially. Egocentrism (of which the soul’s deep-seated distaste for truthfulness is one of the strongest expressions) should be better dealt with prior to any kind of "esoteric training".
