I believe the OP meant, for example, If I played Avallac'h you draw a card. When you over over the card to look at what you drew, I can see the red outline. Based on where that outline is in you hand, I can make a reasonable guess as to what you drew (Special, low/mid unit, high unit/Gold). So, while seeing what is being read on the battlefield is no problem, and should probably be encouraged; seeing effects and highlights on cards in hand is giving information to your opponent. Just watching the the highlights during game (what card turned red when my opponent played that Alzur's Thunder? Oh, 3d from the left. So there's at least two more specials in hand, and likely more) can give away a lot of information to those watching the hand animations more than the battlefield.