OK, I could swear I've seen this theory sketched somewhere: Roche is a servant of higher manipulative forces and is spying (at the least) on Severian. I've skimmed through Borski's book, Wright's book and searched in the archives, but I'm missing it. Regardless, one of the things that has struck me in closely reading the first several chapters is how active much of an active participant Roche is.
Chapter 1: "I would have hidden, but Roche held me..."
Chapter 2: Roche seems to be the one who succeeds in 'reviving' Severian. "...with Roche, then Drotte, then Roche again, breathing into my mouth." "At last I pulled away from Roche and vomited great quantities of black water."
Chapter 9: Roche takes Sev to the House Azure and basically controls the whole transaction: Sev has an overwhelming response to Barbea, the first prostitute introduced, using the loaded word 'golden' to describe her hair three times. But as he's about to say he wants her: "Before I could catch my breath, Roche said, "Let's see some of the others."" Then, after Gracia, "Thecla" comes out. Although at first Sev thinks it is the same Thecla, he is already starting to see through the illusion by the end of his observation: "...though certainly this woman was somewhat shorter." But then the transaction goes ahead. ""It is she you wish, then," our host said. I could not recall speaking. Roche stepped forward with a leather burse, announcing that he would pay for both of us. I watched the coins as he drew them out, waiting to see the gleam of a chrisos. It was not there - there were only a few asimi." So, it seems Roche has been instructed to choose "Thecla" for Sev. Also, the imagery there is interesting: After the intense reaction Sev has to Barbea's "golden" features, he's fixed up with Thecla and looks to see a golden chrisos but sees only silver asimi.
Chapter 12: "The next morning Master Gurloes ordered me to assist him in performing the excruciation. Roche came with us."
Maybe this is all trivial, but the reason I really started looking at it is this bit from chapter three of Shadow:
"There was a loose stone in the floor almost at the foot of my funeral bronze. I pried it up and put the chrisos under it, then muttered an incantation I had learned years before from Roche, a few lines of verse that would hold hidden objects safe:
Where I put you, there you lie,
Never let a stranger spy,
Like glass grow to any eye,
Not of me.
Here be safe, never leave it,
Should a hand come, deceive it,
Let strange eyes not believe it,
Till I see."
This bit's always nagged at me, and I think this is why: It almost sounds like a hypnotic chant. A chrisos=gold=sun is hidden then protected by this incantation: as the sun in Sev is hidden by some kind of post-hypnosis? So he doesn't see, or others? Either way, this passage has always seemed extra important, and this is all that makes sense to me.
And the real Saint Roche was arrested as a spy.
I've read in the archives questions about the significance of Roche's hair color (The Autarch says: ""You have been here previously, have you not? I remember your red hair and high color. Far to the south, in the narrow lands, the savages paint a fire spirit much like you."") and the Roche limit and Roche lobe. It strikes me that (and I am science stupid, so bear with me) this involves binary systems. Is Roche in some way the dying (red) sun balanced by Sev's new? Can anyone out there make anything coherent out of this? Because, as I'm aware, I'm failing miserably...