Do guys think its sexy when a girl can dance?

Heck yes it's a turn on if a girl can dance well. I enjoy a girl grinding as much as the next guy, but a real way to get me going is if she can do ballroom (swing, salsa, tango, waltz, etc. ). As far as "dancing like a slut" goes, yea it will turn me on, but it won't do anything for any other part of my anatomy. So if you really want to wow a guy with your dancing, be classes as well as sexual.

It depends on what you define as good dancing. I have no respect for a girl that only grinds her way through a song.

However, if we are talking about actual dancing, then I think tat as long as it is quality, it should be a turn on.
If we are talking about Hip-Hop dancing, like the competition dance, then it is supposed to be sultery, and can be good.
If we are talking Ballroom, then it is always a turn on. No matter what the situation.
Tap and Ballet also have their places and often imply a hot girl with a firm body.

So, it depends on what your dance is, and if it is legit

I feel like some guys are intimidated by a girl who can dance really well and control her body, especially if she is dancing by herself.

I think she might come off as really independent. But if he can't handle that, you don't want anything to do with him anyway!