I'm absolutely no expert and I don't know anything about how to calculate laser power bla bla bla.... But I think that the Ilda's response (page 4 in your link) is a but unfair. What they say is that the camera's people bring along to gigs are not the responsibility of a the laserist at work. But if you look at the youtube videos of trance energy and just look at the amount of cameras the people bring along.... There's almost a camera per person so I would say that the laserists at work should start thinking about those cameras when they are doing their calculations. But these are just my thoughts and I don't know how those calculations are done. I'm just looking from a ethical point a view.
Life is short.... Ride it hard!!