This posting to the Paleodiet archives has some good points about fiber:
http://maelstrom.stjohns.edu/CGI/wa.exe?A2=ind9710&L=paleodiet&P=R2397&D=0&H
=0&O=D&T=1
(Robīt Beck 24 october)
The description of "floaters" is very close to my own experince.
I feel quite convinced that my guts are doing their cleanout job well.
- Hans