We've been having the odd problem with meetings that hit 15 people or more, in that it can be difficult to communicate, more people are left sitting on topics which are non-specific to them, and inevitably there is a bit of talking between mates and not paying attention going on. This is somewhat exacerbated because facilitators tend to piss people off if they're too harsh/controlling. It can also put off new members because inclusivity and the tendency to encourage them to participate is blunted because a great deal of information is having to be shared in the course of a meeting.
So, how to organise larger meetings most efficiently? Thoughts?
) but some people do and can take it badly, especially around mates, and telling them not to be so sensitive about it may not elicit a helpful reaction. I think a better response can be learned, but when a group’s growing and new people are coming in, especially several at a time, there’s often precious little scope for that kind if thing. 
Can comment on articles and discussions
Hmmm, well I've been to some quite big meetings, and I've facilitated a couple of about 40-odd.
I wouldn't say 15 was very big! People should not be having private conversations in meetings that small, I don't really see what facilitators can do than shut them up. Not rudely but asking them if they can keep private discussion until afterwards. If it's a few problem people doing it every time then people who care about the group or whatever should have words with them.
Facilitators can take special care to get new or quiet-seeming people to give their opinions; the odd go-round can help people get used to having their voice heard. But yeah if people are having private chats with their mates new people won't bother.