Tuolumne
Veteran
Maybe you can appeal to the gallery with the fact that if brightly lit projection screen and monitors are present, you cannot do your job without flash. That should get their attention.
I mean, fighting optical physics is pretty hard if your hands are tied to your back. :bang::bang:
Along these lines, I just shot Newark Mayor Cory Booker's 40th birthday party at a restaurant in the Sony Center in NY. I used my R-D1. I could have used available light, but the photos would not have looked good and it would have been a pain squint-focusing all night long. Instead, I used a bounce flash on the R-D1 and a CV 15mm lens (EFL 21mm on the R-D1) @f5.6 and ISO400. The CV 15mm was set for a hyperfocal distance of about 3ft - infinity, so I didn't have to focus at all. Just point at what I liked and push the button. And with a lens that wide, I didn't even have to look through the viewfinder, just wandered around and checked the view periodically. I think the results speak for themselves.

The rest are here, starting at the bottom of page 2:
http://www.citylightsphoto.com/gallery/8132297_4VYpS#P-2-20
This was the first time in a while I've shot an event with flash, but it couldn't have been done otherwise.
/T