I know what you mean. I cringe when I think back on the many times I was young and made some proclamation where I informed everyone that they had it all wrong. My whole attitude was "It's not like you think, but I'm a benevelont sort, so I'll clue you in." Then I'd sit back and wait for people to realize I was so very, very right, admire me for my insight, and feel grateful to me for sharing it with them. For some reason I was ignored, or saw eyerolls and shared glances among my audience. Sometimes even outright accusations that I didn't know what the hell I was talking about. How rude! Here I was, sharing my pearls of wisdom and this was the thanks I got.
Over time, I was proven wrong often enough that I became more circumspect. There were too many times where I'd say "That never happens," until it did. "I would never," until I did. "My kid doesn't do that," and then... It's quite embarrassing.
Now, I try to reign in my declarative impulses. I say "I hope that doesn't happen, although I know/heard it's happened before." "I used to think I'd never do that, until --." "My kids didn't do that very much, but there was a time or two when they did."
It's kind of cool now. My kids are all over the age of 20, and they sometimes come to me for advice. Often they get it without asking for it. They don't always take my advice, and I understand why, but sometimes they'll tell me that I was right, and they don't always say it like they're amazed. It helps that I'm better at admitting that their situation isn't the exact same situation that I'm drawing from. But I can often steer them in the right direction to get advice from someone who knows what they're talking about. I think it gives extra weight when I come out strongly on a subject.
Mark Twain wrote: When I was a boy of fourteen, my father was so ignorant I could hardly stand to have the old man around. But when I got to be twenty-one, I was astonished at how much he had learned in seven years.
Mark grew up in an era where childhood ended more quickly than it does today in many parts of the world. Think about Luke as a fourteen year old boy who's had an epiphany and is full of the knowledge that he is right on all things, and has the backing of God. He thinks he's an adult now, and he's going to go around telling it like it is and expecting everyone else to fall in line.
Life tends to knock you around, and you can learn from it or buckle down and be an asshole. Luke showed his ass plenty of times on the show. He thinks he's all grown up and is all that, and he got encouragement from Heather all over the place. They both love the drama, and are easily influenced by others. I think that production was playing them both and I hope that they'll eventually realize how much they've been used.