I am trying to figure out whether this is something I can try to bring up or if that it out of line and if so how to bring it up.

She is middle-class, sounds like she had a pretty strict/conservative dad and mom was more permissive from what she has said. I don't think she is focusing on obedience versus teaching--it is more like it has never occurred to her to view it from the lens of teaching. She seems to think that the teaching part is just telling DC what she wants Him/her to do, rather than understanding that you have to show more than tell and that it takes tons of repetition for kids to follow rules. I think she would do well with a more teaching-based approach, but it would be a huge shift for her to see it that way and I think she is so convinced that the kid DOES understand the expectations, but is just being "bad"--versus not being developmentally capable of grasping a lot of her directions and expectations or of being able to practice self-restraint. I think a big part of her image of herself as a mom comes from the idea that she knows her kid, so when I imply that DC doesn't get something that she thinks s/he does, then it is attacking her role as the mom.

So would you like to speak to her about this? Show her some articles or recommend books? Or do you just want to have an informative retort ready the next time she says something?

Also, what kind of culture does she come from? Think ethnically, perhaps, but also in terms of religion (?) or even a pronounced working class (?) background - anything that might shed some light on her focus on "obedience" rather than on her DC learning.

My MB has very unrealistic expectations for her (22-month-old) child. She thinks that if DC "knows s/he isn't supposed to" do something, then DC shouldn't do it. E.g., MB complained that while she was in the bathroom, DC opened a cabinet and dumped out a box of cereal. Today, DC did the same thing, again while MB was out of the room. When I suggest that it would be easier to babyproof things that we don't want DC to get into, she says that we shouldn't have to because DC "knows" not to do that, and wouldn't/doesn't do it when I am in charge. She believes that it is just a discipline issue and that DC needs to learn to obey her better. It's true that DC doesn't get into these things when I am in charge, but that is because I supervise extra closely unless DC is in the babyproofed playroom and when I have to leave the room (e.g., to use the bathroom) I get DC involved with an activity and finish up as quickly as I can.

In general, I think MB just doesn't understand development and seems to expect her child to exercise self control to follow rules rather than knowing that toddlers are impulsive and need to be watched and corrected and redirected.