DIL1991, Because whenever I try to explain the new concepts we usually get the handwave of "yeah yeah I know" and are ignored.
It sounds like you do have a problem being ignored. I would not allow anyone who ignored me or did not follow my rules to childmind. To the rest of us who do as we are asked classes would be to waste time.
When Is News Not Really 'News'?
When a political leader lies on their CV - can you trust them?


. Fortunately our daughter in law is both approachable and kind. She explained why she wanted to do it (as she had with sleeping and other aspects of care), how to do it and then trusted us to do it the when we were caring for Littlest. She even suggested the foods he was least likely to choke on for our shifts! Terrifying at times but we all survived! To be honest I'm not sure it has made much difference now, but who knows, it may have. The key for us was listening and understanding the preferences of the parents and then applying their wishes as much as we could. Would I have gone to grand parenting classes? I might if it had been just one or two and I could make the day and time, approaches evolve and it's good to know current thinking.