It's great to hear about such a positive outcome from circle of friends, I'm really pleased to hear that it can work.
We were asked about doing it for ds1, who has aspergers. I actually declined the offer. I didn't like the idea that other children were going to be talking about him in that way, and when it was discussed with the school SENCo, class teacher and counsellor, I did understand the benefits of it that they were trying to promote. But for some reason, and I'm not sure why, I just had a really strong feeling that it wasn't for us. I'm a big believer in trusting your instinct, so we didn't do it, but the school did a variation of it instead.
They chose a small group of children, 8 of them I think, and although none of them knew it, ds was the target child. There was also one other child that was just very shy and struggling socially, and I think it benefited him too. They talked about things they found hard, how to be a good freind, how they could help eachother and all sorts of things like that, and I prefered it because it actually gave ds some skills to help him cope socially, rather than just teaching the other around him how to cope with/help him. I thought that made a big difference, because ultimately I want ds to be prepared for the things that he will find hard throughout life, and for the fact that not everyone will find him easy to understand.
The school also did other things through PSHE with ds in mind that I think helped, but it was all done in very general terms, and things that other children found hard were talked about too. It meant that they all realised that they have their own differences in some ways, and I think the children really value the differences in eachother.
I think there can be times when children end up being default carers, as well as friends to children with difficulties. It won't always happen, and of course NT children can enjoy being with SN children, but I think it would be doing some very kind and thoughtful children a great disservice if we try and pretend that they always enjoy looking out for their friends with SN, and don't feel any burden at all.
I once had a little girl come up to me when they were in yr3 telling me that she was worried about my ds. She was so sweet! She said she'd tried to play with him but he didn't want to play with her and her friends, and she was worried because he was playing by himself at play time. Ds was capable of joining in with things if he wanted to, but sometimes the other children just weren't doing theing that interested him, so he would prefer to play alone. But when I spoke to this little girls Mum about it, I found out that she was actually really upset and was feeling a responsibility that was beyond her. It would be unfair to dismiss that concern and sense of responsibility by saying that she was just being kind and trying to enjoy ds's company. Adults can find it hard to look after their friends when they are having a bad time, that doesn't mean they are being carers, just that it can be hard.