Honestly, it feels like a lot of hype. People get worked up over every new teaching method, but most just fade away. Is the grid really that different from old math?
Wait, hold on. The grid clicked for your kid in Phoenix of all places? That's wild because I heard the school district out there was fighting over the whole math thing, like some parents were super against it. My cousin teaches in Scottsdale and she said half the staff quit over the new curriculum last year. Maybe the teacher is one of the ones who actually gets it. I'd be curious what grade your kid is in, because I've seen it work better for younger kids who don't have all the old multiplication tricks stuck in their heads.