I'm interested in what people here think explains the teacher's assertions as quoted in the OP.
My theory is that the teacher is a complete nutcase. He's brazenly describing some kind of recent writing "revolution" among math or STEM professionals. He seems to have no concern that he'll be caught out by the more astute parents. What on earth is he thinking? I certainly wouldn't want my kid in a classroom with someone like that.
My charitable assessment could be that he's exaggerating; or that's what he's been told; or he's massively simplifying; or he's putting a marketing spin on it to get your buy-in to head off parent complaints. After all, he didn't choose the curriculum--it was selected by some committee he likely wasn't involved with--he's stuck with it as much as you arm.
You know what it makes me think of? When DD was in 1st grade, she was in literally the worst classroom ever built. But that teacher stood up there on curriculum night and claimed with a straight face that she LOVED her room. She was clearly lying through her teeth because I've been a teacher, and no teacher could love that room. I think she just didn't want us parents all complaining how our students had been relegated to a walking closet crossed with a fishbowl.
On the less charitable side, perhaps he doesn't understand the connection between understanding a concept and being able to explain it. Hopefully this isn't the case.
