Board Thread:Show-Related Questions and Answers/@comment-204.8.200.56-20130220172252/@comment-6195464-20130220172755

August is kind of a dramatic guy... and, sometimes when you throw something like that at someone their reaction (usually shock) makes it impossible to deny anything, whereas, if he had just asked Neal if he was Baelfire outloud, Neal might have had time to control his reaction and play dumb.

And - well, lets be honest... the writers wanted the reveal to be a little more interesting than just... "Hey, Neal! I'm August... I know you're Baelfire!"