good chapter. I liked it.
Byakugan users do use a hand seal to avtivate it. if u watch neji vs hinata u'll see that hinata did used a hand seal before the veins showed up, acutally come to think of it she uses that seal everytime she wants to use byakugan. neji on the other hand uses that seal only out side of a fight not when he is in one. not too sure about sharingan though, don't know how that works.