Maybe I am glad hearing Hyun Joong denied the rumors about dating UEE but that is not to say I am not liking the girl. Maybe I am just shipping him with other actress that is why this denial is a relief for me. Then it is not to say that my ship is true because there is no confirmation after all these years, it is just that there is hope that it may come true in the future.
Anyway, I have watched them in Barefoot Friends and although many have seen the "moments" between HJ and UEE, well, I think he was being his usual self, the caring and sweet guy to the only girl in the group. Let us not forget that she is the only girl. And maybe they look good together that is why viewers liked them.
I don't think HJ will deny a rumor in an interview if it was true. He knew that lying would certainly earned him the ire of the people in the industry if found out true. And if there are possible photos snapped of them together, it would be embarrassing for him and makes him a liar.
this is just my thoughts regarding the news