Is Dominic upset because he missed his chance to look upon the Heart of Magic? Or is he upset because he's regretting his decision to look at all? We would've found out if Katya hadn't started yelling. Dominic isn't the only seer in his house right now.
Luna's "no secrets" policy is one I share with my wife. If there's one thing the both of us have learned from previous failed relationships, it's that communication and openness are very important. Even if it's an unpleasant conversation, it's vital to get whatever's bothering you off your chest and out in the open.
In the case of today's comic, however, it makes for some dramatic tension. At least I think so, but I'm biased because I make the comics around here.
That's all from me for now.