Couple of points and question

Very good points you make :)

Now going back to his reversal in attitude...
You could obviously see the lightbulb go off above his head when the shrink asked him where his dad was. All of the wonderful memories he gave the shrink were involving his mother, and he didn't even realize it until the psychologist asked him why he wasn't mentioning his father. Walt finally realized that his father was absent for most of his childhood. I suppose you could consider it 'patchy,' but i never really thought of it that way...

And YES, i love the predecessor line Oh bernard...

I'd give you my credit card, but I used my AmEx to hit a face I didn't like.

I think the whole point of Walt's behaviour is that he never really liked his dad. He always acts exactly like him, repeats what he says, and sides with him, but he seems to do it out of obligation, not true devotion. There's always an underlying layer of disgust and denial under it all.

On one hand, he's afraid to do anything else, because his father is such an overbearing figure. (I don't mean "afraid" as literally afraid of his father, I mean afraid of new experiences, the unknown.) On the other, he tries to imitate his dad because it would somehow justify his dad's actions. That's why he's so furious with his mother in the beginning - because he just doesn't want to admit his dad's failures. When Frank tells him his dad dropped the burgers on the floor, Walt shushes him. He knows it's the truth, he knows his dad lied about it, he just doesn't want to face it.

So I definitely wouldn't say he "idolises" his dad. He tries to be like him, and to defend him, because it's easier - it's much easier to just agree with someone that controlling than to make your own mind about things. The "Tale of Two Cities" discussion exemplifies that. He doesn't bother reading any of the books he talks about - just repeats his dad's idiotic judgements, because then he doesn't have to face judgement himself. And it doesn't turn out well - he breaks up with Sophie, for example, because his dad pressures him into it, but he regrets it later.

The two incidents - at the psychiatrist's, and seeing his dad with Lili - didn't change anything by themselves. They just helped solidify the knowledge that Walt already had: of how pathetic (in the true sense of that word) his dad really is. So the about-turn is something that's happening throughout the whole film.

As for the duck/pond episode, I doubt it "means" anything, really. It just demonstrates Walt's confusion. And teenagers sometimes do silly or unpredictable things, just for the sake of it. :) Also, since the film seems to be semi-autobiographical, it might be based on a real incident.

"I don't believe you. You're a liar!"

I agree with both prettymaryk and mxpx6703.

I really track Walt's allegience change to three moments in the film.

(1) He sees his dad with Lili. He was in love with her and Frank even could see it. Plus, his dad was brutally obvious in his not caring about Walt's future with Sophie. "You'll make the right decision." Who says that as their advice to their son?

(2) Walt realizes that his dad wasn't around for his childhood when he's talking to the psychiatrist, and his mom was always around. This is also a moment that I question if Bernard really was faithful to Joan because if Walt doesn't remember him being around maybe Bernard was the one who was having affairs.

(3) Bernard fakes a heart attack just to keep Walt on his side. Walt realizes he faked the heart attack when he says "too many veil cutlets," in his response. It's pretty awful to fake a heart attack just because you don't want your son to be mad at you.

Plus, in that hospital scene, Bernard is so cold and indifferent towards Walt. He says, 'you were very emotional when you were younger' when he sees Walt cry. Then, instead of trying to comfort him, he just says, "we can make your room better, and you can have my [book] - as a present." Like "as a present" is supposed to make Walt feel better.

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"When Gotham is ashes, you have my permission to die." — Bane (TDKR)