Let's hope that doesn't start a new string of theatrical theories.And if murder was premeditated it makes no sense why a murderer would want other people to see him, disguised or not. It’s not as if there was only one single access point to the bridge. He had no way of knowing Libby was prepared with her cellphone and caught his image on video or recorded his voice.
Unless the disguise theory comes from the notion the murderer knew and encouraged Libby to participate in some sort of theatrical performance by videoing him, but that’s lightyears away from the facts of the case.
And anyway, I don't see anything odd about the way BG was dressed. It seems perfectly normal for the time of year, rural America.