Let me clarify, it has not actually been confirmed that the whale is a dream. It has been said by a Nintendo representative however that the game starts with Link having a dream and waking up in Skyloft. Exactly like OoT started, with Link having a dream and waking up in Kokiri Forest.
The part about the whale being in the dream is just a theory, albeit a very plausible one. I think the dream encompasses not only the part with the whale, but the scenes with Link falling in darkness and seeing Phi as well. Link has had prophetic dreams before, so why not again?
First of all, Zelda is wearing different clothes from when Link and her go flying and get sucked in the tornado. No matter how you twist it, it's impossible that it's the same event.
Second, the scene with the whale seems very dream-like, with all-white background and a very dream-like effect, no to mention the slo-mo, with Zelda reaching out to Link as she falls. Granted, the slo-mo isn't a great argument, but still.
Third, the scene afterwards with Link falling suddenly has a completely black background. This is very dream-like, as the scene changes with the events and how Link, the dreamer, feels.
Last, I feel the whale looks more like some sort of metaphore for the 'evil' down below, than an actual creature, but this is more my opinion.
This is not a movie. That happens in movies because they take shots at different times, and its real people with mistakes. Games are programmed, they are not gonna randomly program extra clothing on a video game character by accident. Specially the people who make zelda.i didn't mean to offend anyone but people do like to state opinion as fact when it is indeed opinion. which is what it seemed like people on this tread were doing. no it does not look like a dream to me. just because i don't see things your way doesn't mean that i haven't watched the trailer or that i am see something wrong. i'm just suggesting that the two things occur at the same time which is what a lot of people think because that is how it appears to be. and thing about zelda's clothes could just be an accident. that has happened in movies and cartoon shows. i don't think it means anything. sometimes people look too closely and imply things that really mean nothing.
Consider that the scene with Zelda riding with Link and getting sucked into the tornado is the only scene in which that particular article of clothing is absent. If anything seems out of place, it's that scene, not the one with the whale.