After reading about a third of the outstanding messages, I see that most people seem to assume that there is some kind of fundamental change in Silkhorn after Remora's message. I don't think so; I think it's more an "implosion" experience that at last makes denial untenable.
Denial of what? Not just whose body he's in (though he seems to have managed to deny, by and large, even that): but of who's in there with him.
Suggestion for overall mechanism.
1. Silk is scanned into Mainframe.
2a. Horn's body is dying on Green.
2b. Silk's spirit is dying in his body.
3. The Neighbor sends Horn's spirit into Silk's body.
at this point it is *JUST Horn in there*
4. At the West Pole, the scanned Silk reenters the body
-- not from Pig, but from the glass.
We see from the conversations with Horn that Silk is a
reluctant possessor -- he doesn't like to come forward
and show himself.
5. Horn, who is also Silk, spends three volumes and a
year or so evading the two facts, that he's in Silk's
body, and that Silk is in there too.
6. Implosion, and the combined person is Silk or Horn
or Silkhorn or Horn-Silk.
So why does Horn talk so much like Silk before point 4?
Well, he did before, too -- read his dialog in the
pre-Pajarocu scenes of OBW, and remember that his one
outstanding talent in Long Sun is an uncanny ability to
mimic Silk...
*This is WHORL, for discussion of Gene Wolfe's Book of the Long Sun.