I've definitely read other people's comments that use the bs technique of just quoting parts of the blogpost to make it sound like they read it, but didn't really say anything additionally! I'm new here and guilty of upvoting my comments :( I thought I read that as a tip for beginners :( Guess I'll stop doing that now! Thanks for the tips!
It isn't horrible behavior but people usually don't like seeing it, especially when people with more SP do it.
I wish you success in your steemit career :)