I'm not sure I totally agree, penguin, that she meant anything "wrong". posie's post is interesting (if you'll excuse me talking about you here, posie!!). I honestly think that she just doesn't know much about term breastfeeding (which is why MN is great for coming across things that you may not IRL, as they're often done at home where you just don't see it).
"BF an older child, considering the time and effort..."
I remember when DS1 was going to nursery and really needed breakfast before he went. What a bloody hassle that was, versus a 5 minute BF. Older children take a full feed in just a few minutes - no time at all - and there's no effort as they know exactly how to BF, unlike a newborn.
"...has teeny health benefits"
As I've said, no factually correct. In fact, there's loads of health benefits.
"...and certainly not a reason to keep doing so if there are massive social or other side affects.....eg. If a mother was embarrassed about feeding an older toddler then the benefits to that child are not enough to put a mother through that."
No one is putting a mother through anything! It's her own choice! If she's not happy with it, then she shouldn't do it!
"...in our society it's still frowned upon and I think you have to be very committed to carry on past a year."
No, some people frown upon it and some people think it's wonderful. Other people don't care either way. Many people BF toddlers but only at home so other people don't see it - therefore think it doesn't happen. There's nothing "committed" about it. If it works for you both, it's wonderful, healthy, snuggly, cuddly and soooo special. IF you feel like that, it's fabulous!