Re: #2, My understanding of the experiment is that they simply had people assume poses, and then measured their hormone levels. If they really did tell them up front whether the pose was intended to make them feel powerful, that would certainly be an egregious mistake in the methodology, but that wasn't the impression I had from hearing the TED talk.
Actually, I wonder if you could even pull of that version of the experiment without the participants seeing through it ("No really, shrinking into your chair and looking at the floor is a great display of power!").
I didn't really mean to imply that that's how the experiment was initially performed -- or that there's no correlation between poses and hormone levels.
I was more wondering if the results could be replicated with different poses (and a different context).
Then again, if people already "know" that the poses are (relatively) high or low power (hence are able to "see through" false explanations in an alternative study) -- perhaps the mental state is more important than the actual pose.
Actually, I wonder if you could even pull of that version of the experiment without the participants seeing through it ("No really, shrinking into your chair and looking at the floor is a great display of power!").