Although I really enjoyed the demo, I found blocking to be a real pain. Only for team blocking though. As a person who played super Mario rpg's before, I thought that there would be a way to block with your whole team.
We've had the criticism about group-blocking almost as often as the need for making chained attacks easier. I'm presently working on addressing the chained attacks, even a little more drastically than the last patch did. I'm currently thinking on the appropriate means to handle group-blocking. In the Mario & Luigi games it makes a lot of sense since you've got two characters and two buttons assigned to each of them, here it's maybe a little more ambiguous how to "map" that sort of thing, but I do agree that it would be an improvement if group attacks weren't automatically unblockable.