I always thought she went on rambling speeches because that's what Fred used to do.

Hee! Never thought of that.

In the After the Fall comics, we see Illyria spontaneously turning into Fred - she can't control it any longer. Perhaps because, as time goes on, Fred's presence grows stronger within her.

I haven't been reading the comics, but I have kinda been keeping track - the Fred/Illyria plotline is by far the most interesting part of it, IMO.

(Um... by which I mean the plotline about Fred-who-is-also-Illyria. Nothing femslashy. Not at all...)