I've modified Kieran's revisions to the Calc Guide preface and left a
few comments in the file explaining what I did. The result is here:
http://www.odfauthors.org/libreoffice/english/calc-guide/feedback-lo4/cg4-0-preface/view
Good work, Kieran. I'll move on soon to Chapter 1 and try to integrate
changes, questions etc left by Shelagh, Chris, and Kieran.
--Jean