Watching things like this are a bit odd and intimidating to me. I've never ever seen anything like this in a Gurdwara i've been to in my life. To be honest not seen anything like this in 20 or so years, is this a new concept?
Saying that the Evengelicals,and Jehovahs witnesses, Sufis and so on do this singing, chanting, moving about like mad, some say it puts them in a trance...? I do not see any mention of such things occuring the the Darbars of any of the Dhan Guru Sahibs?