I went along to one, seven months after diagnosis and doing a lot of learning for myself, but walked out after ten minutes when it became abundantly clear I was going to learn nothing new, that it was going to aimed at those who knew nothing, and the whole tone was both intrusive and patronising.
They tried to convince me to stay, but had to admit when I could reel off how much I had learnt, that the only reason I'd be staying would because "You'd be such an encouragement to the others." I pointed out if I was giving up a Saturday in term time, it was to be for MY benefit not other peoples!
They also wanted a massive form filling in with far more detail than I was prepared to give to anyone other than my GP to record weight, blood pressure and other facts. Details of "how this makes me feel" are NOT, in my life, to be shared freely unless I chose to. Definitely not if it's forced on me.
It might have been useful if I'd not already learnt a lot.