I can tell their grandmother is all torn up about it:
That was the "not very hip" look -- not exactly something to get torn up about...
We didn't see her face during some of the more puerile moments, but it doesn't matter: shpeculating on what Grandma thought is an exercise in futility -- she's too seasoned a political wife to let embarrassment show for the television cameras even if it were there.
My observation was my own, not one professing to come from reading an elder Bush mind.
If you think the twins was appropriate, came off well, and did good service to W, more power to you -- your opinion. Mine just happens to differ.