I do believe that the vast majority of children who wean before about two had decisions made for them that encouraged that weaning (for example, earlier solids introduction, use of bottles or sippies, etc...). That said, I don't really care either.
People on this board have allowed me to say that my DD "self-weaned" though IN REALITY, she did decide when her last nursing would be, but the limits I put on her *before* that completley changed her nursing timeline (IMO).
I have a good friend who's children have nursed 13, 16 and 15 months. She considers them to have weaned themselves down to one nursing daily and then she pushed that last one. Now, if she wanted to nurse longer, I would have MANY, MANY suggestions to make to change that but she doesn't want to change it, so I don't. KWIM? So, if she wanted to change that for a future child, that would be easy (IMO) but to say that her children didn't cut down *on their own* is pretty meaningless. And especially after the fact saying, "well, if you didn't start bottles at nine months maybe he wouldn't have weaned at 18 months" doesn't even make senseto do, imo.
That said, I don't really even think about CLW until after at least two, probably more like three (not think about doing it, but putting it in that context) because I figure children that age really can't make a *real* long term decision anyway.
Honestly, probably some of my opinions come down to good ole jealousy though. I would LOVE my children to self-wean right at 2.5-3. I get so jealous hearing these wonderful loving stories of self-weanings at 2-2.5 when I think about how HARD it was to nurse through a pg, tandem nurse, deal w/thrush and a two year old, etc... So, chalk up any negative feelings I exhibit to a bad attitude