Well, it looks like I may have been mis-attributing the throwing marshmallows quote. Sandra mentioned that the quote came from a different poster on unschooling.com, Katrina Gutleben (online name katgut). In her book, Parenting a Free Child, Rue Kream verified and attributed the quote to Katrina. At this time, Barbara has not responded to emails trying to clear it up.
I honestly do not know with 100% certainty who the quote belongs to. But I do remember katgut’s posts on unschooling.com and do not remember posts by Barbara (I was taking her word for it and unfortunately the forums do not still exist so there is no way to check).
So I have updated the quote’s attribution. In case anyone is interested in why it has changed.