That's much trickier than you think, because people's reactions are highly contextual. Imagine if someone went on the dance floor who you wouldn't expect to have any dance moves at all, but they are pretty good. They would get extremely positive reactions, so an alien posing as a human watching this would imitate this, but suddenly get a negative reaction because it would be seen as mocking. It's also possible to dance so well that it generates negative reactions like jealousy. Or you can have geeky Napoleon Dynamite dancing - cheesy, inappropriate and flawed, but somehow able to succeed despite itself. This is because quality of dancing isn't wholly intrinsic to the dance itself, it depends on other social factors, like the social identity of the dancer, the self-perception of the audience, the social meaning of the music and the type of dance being performed. For an alien, this would be the hard problem of dancing. What it boils down to is that when knowledge is highly contextual, it's very hard to learn it as a neutral external observer, you have to become a participant - in a way, before you can learn to dance, first you have to learn to be the audience for dance, to become embedded in the social meanings. This might also be the significance of being a good listener before you can become a good conversationalist.